Q.1 Which type of connector is commonly used for connecting a coaxial cable to a TV antenna?
RJ45
BNC
USB Type‑C
DIN
Explanation - BNC connectors are designed for coaxial cables and are widely used in video and radio frequency applications, such as TV antennas.
Correct answer is: BNC
Q.2 A terminal block that can be crimped onto a wire is known as a:
Screw terminal
Barrier strip
Crimp terminal
Push‑in terminal
Explanation - Crimp terminals are pressed onto the stripped end of a wire using a crimping tool to form a secure, conductive connection.
Correct answer is: Crimp terminal
Q.3 Which connector is rated for the highest current among the following?
Mini‑USB
IEC 60320 C13
Anderson Powerpole
RJ45
Explanation - Anderson Powerpole connectors are designed for high‑current applications, often handling up to 45 A or more, whereas the others are low‑current connectors.
Correct answer is: Anderson Powerpole
Q.4 The primary purpose of a shielded terminal is to:
Increase mechanical strength
Provide a ground path for EMI
Reduce resistance
Simplify installation
Explanation - Shielded terminals have an outer conductive layer that can be connected to ground, helping to divert electromagnetic interference away from the signal conductors.
Correct answer is: Provide a ground path for EMI
Q.5 Which of the following connector types uses a latch mechanism to secure the connection?
SMA
M12
Molex Mini‑Fit
D‑sub
Explanation - M12 connectors feature a snap‑in latch that provides a secure, vibration‑resistant connection, commonly used in industrial sensors.
Correct answer is: M12
Q.6 A connector that can carry both power and data signals in a single interface is:
RJ11
HDMI
USB Type‑C
DB9
Explanation - USB‑C supports power delivery up to 100 W and high‑speed data transfer, making it a versatile single‑interface connector.
Correct answer is: USB Type‑C
Q.7 Which material is most commonly used for the contact pins in high‑reliability connectors?
Aluminum
Copper‑tungsten
Gold‑plated brass
Plastic
Explanation - Gold plating prevents oxidation and ensures low contact resistance, while brass provides good mechanical strength.
Correct answer is: Gold‑plated brass
Q.8 What does the term "IP68" indicate about a connector?
It can handle 68 A current
It is waterproof up to 68 m depth
It is dust‑tight and can be immersed in water beyond 1 m
It operates at 68 °C maximum temperature
Explanation - IP68 is an Ingress Protection rating meaning the connector is completely dust‑tight (6) and can be continuously immersed in water beyond 1 m (8).
Correct answer is: It is dust‑tight and can be immersed in water beyond 1 m
Q.9 In a PCB, a "via" used to connect a component terminal to a different layer is known as:
Through‑hole
Blind via
Microvia
Via‑in‑pad
Explanation - A via‑in‑pad is placed directly in the component’s solder pad, allowing the terminal to be connected to internal PCB layers without extra space.
Correct answer is: Via‑in‑pad
Q.10 The standard connector used for Ethernet networking (10/100/1000 Mbps) is:
RJ11
RJ45
USB‑B
DB‑25
Explanation - RJ45 connectors with eight conductors are used for Ethernet cables such as Cat5e, Cat6, and Cat6a.
Correct answer is: RJ45
Q.11 Which of the following is a key advantage of a push‑in (spring‑loaded) terminal over a screw terminal?
Higher current rating
Simpler, faster wiring without tools
Better heat dissipation
Lower cost
Explanation - Push‑in terminals clamp the wire using a spring mechanism, eliminating the need for a screwdriver and reducing installation time.
Correct answer is: Simpler, faster wiring without tools
Q.12 Which connector family is specified by IEC 60320 for connecting appliance power cords?
C‑type
D‑sub
IEC C13/C14
M12
Explanation - IEC 60320 defines the C13 (female) and C14 (male) connectors used for power cords on computers, monitors, and other appliances.
Correct answer is: IEC C13/C14
Q.13 A "keyed" connector is designed to:
Increase current capacity
Prevent incorrect mating
Reduce cost
Provide EMI shielding
Explanation - Keyed connectors have physical features (keys, notches) that only allow insertion in the correct orientation, avoiding mismatches.
Correct answer is: Prevent incorrect mating
Q.14 When selecting a terminal for a high‑temperature environment (up to 200 °C), which material should be avoided?
Copper‑tin alloy
Nickel‑silver
Tin‑plated copper
Gold‑plated brass
Explanation - Tin plating can soften and migrate at temperatures above 150 °C, making it unsuitable for 200 °C applications.
Correct answer is: Tin‑plated copper
Q.15 Which connector type is most suitable for high‑frequency (GHz) microwave applications?
BNC
N‑type
RJ45
USB‑A
Explanation - N‑type connectors are designed for low‑loss performance up to several GHz, making them ideal for microwave systems.
Correct answer is: N‑type
Q.16 A "blind via" in a printed circuit board is used when:
Connecting all layers to the outer surface
Connecting an outer layer to only one inner layer
Connecting two inner layers without reaching outer layers
Providing thermal relief
Explanation - Blind vias start at an outer layer and end at a single inner layer, saving space on the opposite side of the board.
Correct answer is: Connecting an outer layer to only one inner layer
Q.17 The term "contact resistance" of a terminal refers to:
Mechanical wear over time
Electrical resistance at the metal‑to‑metal interface
Thermal conductivity
Voltage rating
Explanation - Contact resistance is the small resistance introduced where two conductive surfaces meet, influencing overall circuit performance.
Correct answer is: Electrical resistance at the metal‑to‑metal interface
Q.18 Which of the following connector series is specifically designed for automotive applications with a locking mechanism?
Molex Mini‑Fit
JST PH
Deutsch DT series
USB‑Micro
Explanation - Deutsch DT series connectors provide a robust locking feature and are widely used in automotive wiring harnesses.
Correct answer is: Deutsch DT series
Q.19 For a connector that must operate in a corrosive marine environment, which plating is preferred?
Tin
Nickel
Gold
Silver
Explanation - Nickel plating offers good corrosion resistance in salty atmospheres, making it suitable for marine applications.
Correct answer is: Nickel
Q.20 The main advantage of a “screw‑type” terminal is:
Tool‑less installation
High vibration resistance
Fast connection of multiple wires
Low manufacturing cost
Explanation - Screw terminals clamp the wire tightly, providing a reliable connection that resists loosening under vibration.
Correct answer is: High vibration resistance
Q.21 Which connector family is defined by the IEC 61076‑3‑104 standard?
M8/M12 circular connectors
D‑subminiature
RJ45
USB
Explanation - IEC 61076‑3‑104 specifies the dimensions, performance, and coding for M8 and M12 circular connectors used in industrial automation.
Correct answer is: M8/M12 circular connectors
Q.22 A terminal block that uses a spring clamp instead of a screw is called a:
Push‑in terminal
Spring‑loaded terminal
Barrier strip
Insulation displacement connector
Explanation - Spring‑loaded terminals provide a secure connection by applying constant pressure via a spring mechanism, eliminating the need for screws.
Correct answer is: Spring‑loaded terminal
Q.23 In a multi‑pin connector, the term "polarization" refers to:
The color of the pins
The arrangement that prevents incorrect insertion
The voltage rating
The type of shielding
Explanation - Polarization ensures that the connector can only be mated in the correct orientation, often using asymmetrical keying.
Correct answer is: The arrangement that prevents incorrect insertion
Q.24 Which of the following is NOT a common method of attaching a wire to a terminal?
Crimping
Soldering
Spot welding
Adhesive bonding
Explanation - Adhesive bonding is not typically used for electrical connections because it does not provide a reliable conductive path.
Correct answer is: Adhesive bonding
Q.25 A "high‑density" terminal block is designed to:
Carry higher current
Fit more circuits in a smaller board area
Provide better heat dissipation
Offer better shielding
Explanation - High‑density terminal blocks have reduced pitch (spacing) between terminals, allowing more connections on a compact PCB.
Correct answer is: Fit more circuits in a smaller board area
Q.26 The IEC 60906‑1 standard defines which type of connector?
International 2‑pin plug
Power over Ethernet
Coaxial RF
USB‑C
Explanation - IEC 60906‑1 specifies a universal 2‑pole plug and socket system for low‑power devices, intended as a global standard.
Correct answer is: International 2‑pin plug
Q.27 In a terminal strip, the term "bus bar" refers to:
A protective cover
A conductive strip that distributes power to multiple terminals
An insulating spacer
A type of screw
Explanation - Bus bars are thick conductive bars that carry current to several terminal points within a strip.
Correct answer is: A conductive strip that distributes power to multiple terminals
Q.28 Which connector is specifically designed for connecting fiber‑optic cables?
LC
RJ45
BNC
D‑sub
Explanation - LC (Lucent Connector) is a small form‑factor fiber‑optic connector widely used in telecom and data communications.
Correct answer is: LC
Q.29 A connector with a "keyway" is used to:
Increase current rating
Prevent accidental disconnection
Ensure correct mating orientation
Reduce electromagnetic emissions
Explanation - A keyway is a physical notch that aligns with a corresponding protrusion, guaranteeing the connector is inserted only one way.
Correct answer is: Ensure correct mating orientation
Q.30 Which of the following is a common rating for a standard PCB‑mount terminal block?
10 A
2 A
20 A
30 A
Explanation - Many PCB‑mount terminal blocks are rated for around 10 A, balancing size and current‑carrying capability for typical board applications.
Correct answer is: 10 A
Q.31 The main purpose of a “strain relief” in a connector assembly is to:
Increase electrical conductivity
Prevent mechanical stress on the solder joints
Improve heat dissipation
Reduce electromagnetic interference
Explanation - Strain relief components absorb pulling forces, protecting the soldered connections from fatigue and breakage.
Correct answer is: Prevent mechanical stress on the solder joints
Q.32 Which of the following connectors is NOT typically used for power delivery?
IEC 60320 C19
M8
IEC 60320 C13
HDMI
Explanation - HDMI is primarily a video/audio interface, not intended for power delivery, whereas the IEC connectors are designed for mains power.
Correct answer is: HDMI
Q.33 A "DIN" connector is best described as:
A circular connector for high‑frequency signals
A multi‑pin connector originally standardized by the Deutsches Institut für Normung
A type of coaxial connector
A USB variant
Explanation - DIN connectors were standardized in Germany and are used for audio, video, and data connections with various pin counts.
Correct answer is: A multi‑pin connector originally standardized by the Deutsches Institut für Normung
Q.34 The most common pitch (center‑to‑center spacing) for a standard 0.1 in (2.54 mm) PCB header is:
0.5 mm
1.27 mm
2.54 mm
5.08 mm
Explanation - A 0.1 in pitch equals 2.54 mm, which is the standard spacing for many through‑hole and surface‑mount headers.
Correct answer is: 2.54 mm
Q.35 Which connector family uses a locking tab and is commonly found in aerospace applications?
D‑sub
M12
MIL‑DTL‑38999
RJ45
Explanation - MIL‑DTL‑38999 connectors feature a robust locking tab and are designed for harsh aerospace environments.
Correct answer is: MIL‑DTL‑38999
Q.36 When a connector is described as “IP20”, it means:
Dust‑tight but no water protection
Protected against water splashes
Fully sealed against dust and water
Only suitable for indoor use
Explanation - IP20 indicates protection against solid objects larger than 12 mm (dust‑tight) but no protection against water ingress.
Correct answer is: Dust‑tight but no water protection
Q.37 Which type of connector is commonly used for connecting a motherboard to a power supply unit (ATX)?
Molex 4‑pin
PCIe 8‑pin
ATX 24‑pin
USB‑C
Explanation - The ATX 24‑pin connector supplies main power from the PSU to the motherboard.
Correct answer is: ATX 24‑pin
Q.38 The primary benefit of a “blind mate” connector is:
Higher current rating
No need for alignment pins during mating
Lower cost
Better heat resistance
Explanation - Blind‑mate connectors are designed to engage automatically without visual alignment, useful in tight spaces and automated assembly.
Correct answer is: No need for alignment pins during mating
Q.39 Which material is most suitable for a terminal that must operate in a high‑frequency (RF) environment?
Aluminum
Copper‑tungsten
Stainless steel
Nickel‑silver
Explanation - Copper‑tungsten maintains conductivity at high frequencies while providing mechanical strength, making it ideal for RF terminals.
Correct answer is: Copper‑tungsten
Q.40 A connector that can be mated and demated more than 10,000 times is said to have a:
High voltage rating
High insertion cycle rating
Low contact resistance
Large shielding
Explanation - Insertion cycle rating specifies the number of mating cycles a connector can reliably endure without performance degradation.
Correct answer is: High insertion cycle rating
Q.41 Which of the following connector types uses a “bayonet” locking mechanism?
BNC
RCA
USB‑B
D‑sub
Explanation - BNC connectors lock by twisting a pin and sleeve together, forming a bayonet coupling.
Correct answer is: BNC
Q.42 The term "copper alloy" in a terminal indicates:
The terminal is made of pure copper
Copper mixed with other metals to improve strength or corrosion resistance
Copper coated with tin
Copper with a gold finish
Explanation - Alloying copper (e.g., with tin, silver, or nickel) enhances mechanical properties and resistance to oxidation.
Correct answer is: Copper mixed with other metals to improve strength or corrosion resistance
Q.43 A connector rated for 250 V AC is unsuitable for which of the following applications?
Connecting a 120 V household lamp
Powering a 240 V industrial motor
Supplying 12 V DC to a microcontroller
Connecting a 230 V AC appliance
Explanation - While the voltage rating is higher than needed, the connector may be physically too large and unnecessary for low‑voltage DC; a low‑voltage connector is preferred.
Correct answer is: Supplying 12 V DC to a microcontroller
Q.44 In a PCB layout, the term "keep‑out area" around a connector means:
No copper should be placed in this area
No other components should be placed too close
No drilling is allowed
No solder mask is applied
Explanation - A keep‑out area ensures sufficient clearance for mechanical stability, heat, and electrical isolation around the connector.
Correct answer is: No other components should be placed too close
Q.45 Which of the following is a common feature of a “circular” connector family?
Rectangular shape
Keyed latching mechanism
Twist‑lock coupling
Flat ribbon cable interface
Explanation - Circular connectors often incorporate a keyed latch or bayonet for secure, orientation‑specific mating.
Correct answer is: Keyed latching mechanism
Q.46 A connector that is specified as "24‑AWG compatible" is suitable for wires of which maximum diameter?
0.020 in (0.5 mm)
0.040 in (1.0 mm)
0.020 mm
0.080 in (2.0 mm)
Explanation - 24‑AWG wire has a diameter of roughly 0.020 in (0.5 mm); terminals marked for 24‑AWG are designed to accept that size.
Correct answer is: 0.020 in (0.5 mm)
Q.47 Which connector is defined by the standard IEC 60320 C15/C16?
High‑temperature power connector for appliances
Standard Ethernet connector
USB Power Delivery connector
Audio jack
Explanation - C15/C16 connectors are rated for up to 120 °C and are used for high‑temperature power connections like coffee makers.
Correct answer is: High‑temperature power connector for appliances
Q.48 A "ferrule" in a terminal assembly is used to:
Provide electromagnetic shielding
Increase the mechanical strength of the wire termination
Reduce contact resistance
Serve as a visual indicator
Explanation - Ferrules are metal sleeves crimped onto stranded wire ends to prevent fraying and maintain a solid connection.
Correct answer is: Increase the mechanical strength of the wire termination
Q.49 When a connector is described as "shielded" it means:
It has a protective plastic housing
It contains a conductive layer that grounds electromagnetic interference
It is water‑resistant
It can handle higher current
Explanation - Shielded connectors use a metal braid or foil to confine EMI and can be grounded to improve signal integrity.
Correct answer is: It contains a conductive layer that grounds electromagnetic interference
Q.50 Which of the following is a standard connector for high‑speed serial data (e.g., SATA)?
Molex KK
SATA power connector
HDMI
RJ45
Explanation - SATA connectors provide both power and data interfaces for storage devices, with a distinct L‑shaped design.
Correct answer is: SATA power connector
Q.51 The term "pitch" in a connector refers to:
The maximum current rating
The distance between the centers of adjacent pins
The voltage rating
The type of material used
Explanation - Pitch is a key dimension that determines how densely pins are placed on a connector.
Correct answer is: The distance between the centers of adjacent pins
Q.52 A connector that uses a "screw‑type" locking mechanism is most suitable for:
High‑frequency RF signals
Applications where frequent mating/unmating is required
Vibration‑prone environments
Low‑cost consumer electronics
Explanation - Screw‑type locks maintain a tight mechanical connection, resisting loosening from vibration.
Correct answer is: Vibration‑prone environments
Q.53 Which of the following is a typical current rating for a standard RJ45 Ethernet jack?
0.5 A
1 A
2 A
5 A
Explanation - RJ45 jacks are generally rated for about 1 A per contact, sufficient for PoE applications up to 30 W.
Correct answer is: 1 A
Q.54 A connector that complies with the UL 94V‑0 rating is referring to:
Flame‑retardant plastic material
Voltage rating
Current capacity
Mechanical durability
Explanation - UL 94V‑0 is a safety standard indicating that the plastic material self‑extinguishes quickly after ignition.
Correct answer is: Flame‑retardant plastic material
Q.55 Which connector is typically used for a laptop's external display (HD video)?
Mini‑DisplayPort
RJ45
USB‑A
M8
Explanation - Mini‑DisplayPort (or its variant, Thunderbolt) is a common connector for transmitting high‑definition video from laptops.
Correct answer is: Mini‑DisplayPort
Q.56 When a terminal is described as "solder‑type", it means:
It requires a screw to clamp the wire
The wire is attached by melting solder onto the terminal
It uses a spring mechanism
It has a built‑in fuse
Explanation - Solder‑type terminals rely on solder to create an electrical and mechanical bond between the wire and the terminal.
Correct answer is: The wire is attached by melting solder onto the terminal
Q.57 Which of the following connectors is defined by the IEC 61076‑2‑101 standard?
M12
USB‑C
D‑sub
RJ45
Explanation - IEC 61076‑2‑101 specifies the M12 connector family used in industrial automation for sensor and actuator connections.
Correct answer is: M12
Q.58 A connector that incorporates a "spring‑loaded pin" is primarily used for:
High‑current power distribution
Quick, tool‑free mating in test fixtures
Waterproof applications
RF signal transmission
Explanation - Spring‑loaded pins (pogo pins) enable rapid, reliable contacts in testing and programming without tools.
Correct answer is: Quick, tool‑free mating in test fixtures
Q.59 Which connector type is most commonly used for a standard 5‑V USB power supply?
USB‑C
Micro‑USB
USB‑A
Mini‑USB
Explanation - USB‑A connectors are the traditional host port that supplies 5 V power in most chargers and computers.
Correct answer is: USB‑A
Q.60 The term "IP rating" does NOT cover which of the following aspects?
Dust protection
Water ingress protection
Thermal resistance
Mechanical impact resistance
Explanation - IP ratings address ingress of solids (dust) and liquids (water) only, not mechanical impact.
Correct answer is: Mechanical impact resistance
Q.61 A "quick‑disconnect" terminal block is best suited for:
Permanent wiring
Frequent maintenance or reconfiguration
High‑temperature environments
High‑frequency signal transmission
Explanation - Quick‑disconnect blocks allow wires to be inserted or removed without tools, ideal for modular or serviceable systems.
Correct answer is: Frequent maintenance or reconfiguration
Q.62 Which of the following connectors is typically used for a high‑definition audio/video interface (e.g., Blu‑ray players)?
HDMI
RJ45
DB‑25
USB‑B
Explanation - HDMI carries uncompressed video and audio, widely used in consumer AV equipment.
Correct answer is: HDMI
Q.63 In a connector datasheet, "Mating Force" refers to:
The force required to pull the connector apart
The force required to insert the connector
The force the connector can withstand without damage
The torque needed for the screws
Explanation - Mating force is the amount of axial force needed to bring two connector halves together for proper engagement.
Correct answer is: The force required to insert the connector
Q.64 Which of these connector types is typically rated for the highest voltage (up to 600 V AC)?
IEC 60320 C13
N‑type
IEC 60309 (blue)
USB‑C
Explanation - IEC 60309 blue connectors are rated for 600 V AC, commonly used in industrial power distribution.
Correct answer is: IEC 60309 (blue)
Q.65 The term "wire gauge" in relation to terminals most directly affects:
Connector color
Mechanical size of the terminal barrel
Maximum voltage rating
Frequency response
Explanation - Wire gauge determines the physical diameter of the conductor, which must match the terminal's barrel size for a proper fit.
Correct answer is: Mechanical size of the terminal barrel
Q.66 A connector with a "push‑pull" latch mechanism is designed to:
Provide a waterproof seal
Allow quick insertion and secure locking
Increase current rating
Reduce electromagnetic emissions
Explanation - Push‑pull latches enable rapid connection while ensuring the connector stays locked during operation.
Correct answer is: Allow quick insertion and secure locking
Q.67 Which of the following connectors is specifically designed for automotive diagnostic communication (OBD‑II)?
USB‑A
RCA
D‑sub 9‑pin
Molex Mini‑Fit
Explanation - The OBD‑II port uses a 9‑pin D‑sub connector for vehicle diagnostics.
Correct answer is: D‑sub 9‑pin
Q.68 When a terminal is described as "UL listed", it means:
It meets specific safety standards set by Underwriters Laboratories
It is made of ultra‑light material
It can handle unlimited current
It is only for indoor use
Explanation - UL listing indicates the component has passed UL's safety testing for electrical and fire hazards.
Correct answer is: It meets specific safety standards set by Underwriters Laboratories
Q.69 A "bayonet" connector is typically used for which of the following applications?
High‑speed data
RF coaxial connections
Power distribution
Audio line‑level signals
Explanation - Bayonet connectors like BNC are widely used for RF and video coaxial applications due to their secure locking.
Correct answer is: RF coaxial connections
Q.70 The purpose of a “fuse” integrated into a connector assembly is to:
Provide mechanical support
Protect downstream circuitry from over‑current
Improve signal integrity
Reduce connector weight
Explanation - An integrated fuse will open the circuit when current exceeds a safe level, safeguarding components.
Correct answer is: Protect downstream circuitry from over‑current
Q.71 Which connector type is most appropriate for a high‑speed data bus such as PCI‑Express?
Molex Mini‑Fit
SATA
PCIe edge connector
RJ45
Explanation - PCIe edge connectors provide the required high‑bandwidth, low‑impedance connection for computer expansion cards.
Correct answer is: PCIe edge connector
Q.72 A terminal rated for "30 °C to 105 °C" specifies:
The operating temperature range of the terminal material
The temperature of the soldering process
The maximum temperature of the wire insulation
The ambient temperature where the connector can be stored
Explanation - This rating indicates the terminal can function reliably within that temperature span during normal operation.
Correct answer is: The operating temperature range of the terminal material
Q.73 Which connector series is commonly used for connecting LED strips in hobby electronics?
M12
JST SM
DB‑9
HDMI
Explanation - JST SM (also known as JST 2.54 mm) connectors are compact and frequently used for low‑power LED strip connections.
Correct answer is: JST SM
Q.74 A "wire‑to‑board" connector is designed to:
Connect two wires together
Mount a cable directly onto a PCB without a separate plug
Provide a waterproof seal
Increase signal bandwidth
Explanation - Wire‑to‑board connectors have contacts that accept stripped wires directly on the PCB, simplifying assembly.
Correct answer is: Mount a cable directly onto a PCB without a separate plug
Q.75 The term "keyed" in a terminal block indicates:
A built‑in fuse
Physical features that prevent incorrect wire insertion
Higher current rating
A special coating for corrosion resistance
Explanation - Keyed terminals have slots or notches that guide wires into the correct orientation, avoiding wiring errors.
Correct answer is: Physical features that prevent incorrect wire insertion
Q.76 Which connector is most commonly used for connecting a computer's internal hard drive to the motherboard?
SATA
USB‑C
RJ45
M12
Explanation - SATA connectors provide both power and data interfaces for 2.5‑inch and 3.5‑inch drives.
Correct answer is: SATA
Q.77 A connector rated for "IP67" can be:
Submerged in water up to 1 m for 30 minutes
Fully dust‑tight and immersed beyond 1 m
Protected against rain only
Used only in indoor environments
Explanation - IP67 indicates total protection from dust and the ability to be submerged in up to 1 m of water for 30 minutes.
Correct answer is: Fully dust‑tight and immersed beyond 1 m
Q.78 Which of the following connector families is specifically designed for high‑temperature (up to 250 °C) applications?
M8
IEC 60320 C15/C16
USB‑C
RJ45
Explanation - C15/C16 connectors are rated for 250 °C and are used in appliances that generate high heat.
Correct answer is: IEC 60320 C15/C16
Q.79 In a connector assembly, a "gasket" is primarily used to:
Secure the connector mechanically
Prevent ingress of dust and moisture
Increase electrical conductivity
Facilitate heat dissipation
Explanation - Gaskets provide sealing between connector halves to achieve a specific IP rating.
Correct answer is: Prevent ingress of dust and moisture
Q.80 A "double‑row" connector typically provides:
Higher voltage rating
More pins in the same footprint
Lower insertion force
Better shielding
Explanation - Double‑row (or staggered) configurations double the pin count without increasing connector size.
Correct answer is: More pins in the same footprint
Q.81 Which connector is commonly used for low‑voltage power distribution on a breadboard?
Molex KK
RJ45
DB‑9
HDMI
Explanation - Molex KK series headers and sockets are widely used for prototyping with breadboards and perfboards.
Correct answer is: Molex KK
Q.82 The term "contact bounce" in a connector context refers to:
Mechanical vibration of the connector
Rapid make‑and‑break of the contact when pressed
Electrical noise caused by EMI
Heat generated during current flow
Explanation - Contact bounce is a mechanical phenomenon where the contacts temporarily separate after initial closure, causing signal glitches.
Correct answer is: Rapid make‑and‑break of the contact when pressed
Q.83 A terminal block marked "30 A, 600 V" indicates:
Maximum current of 30 A and maximum voltage of 600 V
Minimum current of 30 A and maximum voltage of 600 V
Maximum power of 30 W at 600 V
Rated for 30 A only at 600 °C
Explanation - The rating specifies the highest continuous current and voltage the terminal block can safely handle.
Correct answer is: Maximum current of 30 A and maximum voltage of 600 V
Q.84 Which connector is used for a standard telephone line (analog voice)?
RJ11
RJ45
USB‑B
HDMI
Explanation - RJ11 connectors have 4‑6 positions and are used for single‑line telephone connections.
Correct answer is: RJ11
Q.85 When a connector specification lists "Mating cycles: 5,000", it means:
The connector can be used for 5 kW of power
The connector will last for at least 5,000 insertions and removals
The connector can operate at frequencies up to 5 kHz
The connector has a 5 kΩ resistance
Explanation - Mating cycles quantify the durability of a connector’s mechanical engagement mechanism.
Correct answer is: The connector will last for at least 5,000 insertions and removals
Q.86 Which of the following is a common method for terminating a wire to a PCB pad without a separate connector?
Solder‑wire attachment
Crimping
Press‑fit
Insulation displacement
Explanation - Direct soldering of the stripped wire end to a PCB pad is a simple, connector‑free method of termination.
Correct answer is: Solder‑wire attachment
Q.87 A connector that uses a "locking tab" and a "cable clamp" is designed to:
Provide water resistance
Secure the cable mechanically and electrically
Increase current rating
Allow high‑frequency signal transmission
Explanation - Locking tabs hold the connector halves together, while cable clamps prevent strain on the wire termination.
Correct answer is: Secure the cable mechanically and electrically
Q.88 Which type of connector is typically used for connecting a microphone to an audio interface?
XLR
RJ45
USB‑C
HDMI
Explanation - XLR connectors provide balanced audio connections and are standard for professional microphones.
Correct answer is: XLR
Q.89 A terminal that is described as "screw‑type, insulated" means:
The screw is made of insulating material
The terminal includes an insulating barrier to prevent accidental contact
It cannot be used with live circuits
It is only for low‑voltage applications
Explanation - Insulated terminals have a non‑conductive housing around the screw to improve safety.
Correct answer is: The terminal includes an insulating barrier to prevent accidental contact
Q.90 In high‑frequency applications, why are gold‑plated contacts preferred?
Gold has the lowest resistance of all metals
Gold does not oxidize, preserving low contact resistance
Gold is cheaper than copper
Gold can handle higher temperatures
Explanation - Gold plating prevents oxidation, ensuring stable electrical performance at high frequencies.
Correct answer is: Gold does not oxidize, preserving low contact resistance
Q.91 A connector with a "circular" form factor and a 4‑pin configuration is most likely a:
M4
M8
M12
M14
Explanation - M8 connectors typically have 4 pins and are used for sensors and actuators in industrial automation.
Correct answer is: M8
Q.92 Which of the following is an advantage of a "blind mate" connector over a "screw‑type" connector?
Higher current rating
No need for alignment during assembly
Better shielding performance
Lower cost
Explanation - Blind‑mate connectors can be inserted without visual alignment, saving time in automated production.
Correct answer is: No need for alignment during assembly
Q.93 A terminal block that is specified as "screw‑type, 2.5 mm pitch" is designed for:
Connecting 2.5 mm² wire
Mounting on a PCB with 2.5 mm spacing between terminals
Handling 2.5 A current
Operating at 2.5 kHz frequency
Explanation - Pitch refers to the center‑to‑center distance between adjacent terminals on the block.
Correct answer is: Mounting on a PCB with 2.5 mm spacing between terminals
Q.94 Which connector type is commonly used for the power input of a desktop computer?
IEC 60320 C14
USB‑C
RJ45
HDMI
Explanation - The IEC C14 inlet is the standard power entry for most desktop computers and monitors.
Correct answer is: IEC 60320 C14
Q.95 The primary reason for using a "shielded" terminal block in an industrial control panel is to:
Reduce heat buildup
Prevent accidental contact
Minimize electromagnetic interference (EMI)
Increase current capacity
Explanation - Shielded blocks provide a grounded conductive barrier that reduces EMI affecting nearby circuits.
Correct answer is: Minimize electromagnetic interference (EMI)
Q.96 Which connector family is standardized by the IEC 60903 series for use in power distribution?
IEC 60309
IEC 60320
IEC 60903
IEC 61076
Explanation - IEC 60309 defines industrial plugs and sockets for power distribution, often color‑coded for voltage and frequency.
Correct answer is: IEC 60309
Q.97 When a connector specification lists "contact resistance ≤ 10 mΩ", it indicates:
The resistance of the entire connector is less than 10 mΩ
Each individual contact adds no more than 10 mΩ of resistance
The connector can handle up to 10 mA current
The connector must be used at temperatures below 10 °C
Explanation - Contact resistance is the resistance introduced at the point where two conductors meet, measured per contact.
Correct answer is: Each individual contact adds no more than 10 mΩ of resistance
Q.98 A "wire‑to‑wire" connector (often called a splice) is best suited for:
Permanent board mounting
Connecting two wires together without a PCB
High‑frequency signal transmission
Power distribution over 400 V
Explanation - Wire‑to‑wire connectors provide a quick, tool‑free method to join two conductors directly.
Correct answer is: Connecting two wires together without a PCB
Q.99 Which connector is typically used for a computer's mouse and keyboard ports?
PS/2
RJ45
HDMI
USB‑C
Explanation - The PS/2 connector is a 6‑pin mini‑D‑sub used historically for keyboards and mice.
Correct answer is: PS/2
Q.100 The term "dielectric strength" of a connector refers to:
The mechanical strength of the plastic housing
The maximum voltage the insulation can withstand without breakdown
The current rating of the contacts
The resistance to corrosion
Explanation - Dielectric strength is a measure of an insulating material’s ability to resist electric breakdown.
Correct answer is: The maximum voltage the insulation can withstand without breakdown
Q.101 Which of the following connectors is designed for high‑speed serial communication up to 10 Gbps?
USB‑C
RJ45
SATA
M12 X‑coded
Explanation - M12 X‑coded connectors support up to 10 Gbps Ethernet and are used in industrial automation.
Correct answer is: M12 X‑coded
Q.102 A terminal marked "UL94 V‑0" indicates:
It meets a specific fire‑safety flame rating
It can handle 0 V voltage
It is rated for 0 A current
It has zero electromagnetic emissions
Explanation - UL94 V‑0 is a flame‑retardant classification where the material self‑extinguishes within 10 seconds after ignition.
Correct answer is: It meets a specific fire‑safety flame rating
Q.103 Which connector type is used for a standard 3.5 mm audio jack?
RCA
XLR
TRS
DB‑9
Explanation - TRS (Tip‑Ring‑Sleeve) connectors are the standard 3.5 mm audio jacks for stereo signals.
Correct answer is: TRS
Q.104 A "keyed" circular connector with a 12‑pin layout is most likely part of which series?
M8
M12
M16
M24
Explanation - M12 connectors often come in 4, 5, 8, 12‑pin keyed versions for industrial sensors and actuators.
Correct answer is: M12
Q.105 When a terminal is rated for "30 °C to 105 °C", what does the lower limit (30 °C) signify?
The minimum ambient temperature for safe operation
The temperature at which the terminal melts
The temperature below which the terminal loses conductivity
The temperature range of the solder used
Explanation - Below the lower limit, material properties may change (e.g., become brittle), affecting reliability.
Correct answer is: The minimum ambient temperature for safe operation
Q.106 Which connector is commonly used for connecting a laptop to an external display via VGA?
HDMI
DVI
VGA
DisplayPort
Explanation - VGA (15‑pin D‑sub) is a legacy analog video connector still used for many external displays.
Correct answer is: VGA
Q.107 The main advantage of a "solderless" terminal is:
Higher current rating
Faster assembly without a soldering process
Better heat resistance
Improved shielding
Explanation - Solderless (crimp or screw) terminals eliminate the need for solder, reducing assembly time and heat exposure.
Correct answer is: Faster assembly without a soldering process
Q.108 Which connector family uses a "D‑sub" form factor and is widely used for serial RS‑232 communication?
DB‑9
RJ45
M12
USB‑B
Explanation - DB‑9 (9‑pin D‑sub) is the traditional connector for RS‑232 serial ports.
Correct answer is: DB‑9
Q.109 A terminal block labeled "2‑pole, screw‑type" provides:
Two separate electrically isolated terminals
Two poles that are internally connected
A single pole with two screws
Four poles
Explanation - A 2‑pole block has two independent terminals, each with its own screw for separate connections.
Correct answer is: Two separate electrically isolated terminals
Q.110 Which of the following is NOT a typical feature of a high‑frequency connector?
Low dielectric constant insulator
Gold‑plated contacts
Large contact area
Precise impedance control
Explanation - High‑frequency connectors aim for minimal contact area to reduce parasitic capacitance; large areas increase loss.
Correct answer is: Large contact area
Q.111 The term "back‑shell" in a connector refers to:
The inner contact pins
The protective metal housing that can be bolted to a panel
The plastic cover
The cable strain relief
Explanation - A back‑shell provides mechanical mounting and shielding for the connector.
Correct answer is: The protective metal housing that can be bolted to a panel
Q.112 A connector rated for "IP20" can be safely used:
In dusty outdoor environments
In dry indoor environments without water exposure
Underwater up to 2 m depth
In high‑humidity conditions
Explanation - IP20 offers protection against solid objects larger than 12 mm but provides no water protection.
Correct answer is: In dry indoor environments without water exposure
Q.113 Which connector is often used for connecting a power supply to a motherboard in a PC?
ATX 24‑pin
Molex 4‑pin
PCIe 8‑pin
USB‑C
Explanation - The ATX 24‑pin connector delivers main power from the PSU to the motherboard.
Correct answer is: ATX 24‑pin
Q.114 In a connector, the "keying" feature is primarily intended to:
Increase current capacity
Prevent incorrect mating orientation
Improve thermal performance
Reduce electromagnetic interference
Explanation - Keying provides physical guides that only allow the connector to be inserted one way.
Correct answer is: Prevent incorrect mating orientation
Q.115 Which of the following is a typical current rating for a small‑signal, 2‑pin PCB terminal block?
0.5 A
5 A
10 A
20 A
Explanation - Small‑signal terminal blocks are often rated for low currents, typically around 0.5 A per contact.
Correct answer is: 0.5 A
Q.116 A connector with a "twist‑lock" mechanism is best described as:
A connector that twists to lock in place, providing a secure connection
A connector that snaps together without any rotation
A connector that uses a screw to secure the halves
A connector that relies on magnetic attraction
Explanation - Twist‑lock connectors (e.g., some circular industrial connectors) require a quarter‑turn twist to lock.
Correct answer is: A connector that twists to lock in place, providing a secure connection
Q.117 Which connector type is specifically designed for high‑current battery connections in electric vehicles?
Anderson Powerpole
RJ45
USB‑C
M12
Explanation - Anderson Powerpole connectors handle high currents (up to 45 A or more) and are common in EV battery systems.
Correct answer is: Anderson Powerpole
Q.118 The term "strain‑relief" in a connector assembly is used to describe:
A feature that reduces electromagnetic interference
A mechanical element that prevents cable pull forces from stressing the contacts
A type of insulation material
A method of heat dissipation
Explanation - Strain‑relief components protect the termination from mechanical stress caused by cable movement.
Correct answer is: A mechanical element that prevents cable pull forces from stressing the contacts
Q.119 A connector specified as "24‑V DC, 10 A" is suitable for which of the following applications?
Powering a 12 V automotive headlamp
Supplying a 24 V industrial sensor
Charging a 5 V USB device
Running a 240 V AC motor
Explanation - The connector's voltage and current ratings match a 24 V DC sensor requiring up to 10 A.
Correct answer is: Supplying a 24 V industrial sensor
Q.120 Which connector type uses a "bayonet" locking mechanism and is common in video applications?
BNC
RJ45
USB‑C
M8
Explanation - BNC connectors lock by a twist‑lock bayonet mechanism and are widely used for video signals.
Correct answer is: BNC
Q.121 The primary purpose of a "ground" pin in a multi‑pin connector is to:
Carry the main signal
Provide a reference voltage and safety path for fault currents
Increase the connector’s mechanical strength
Reduce the number of pins needed
Explanation - Ground pins ensure a common reference point and help protect equipment by safely conducting fault currents.
Correct answer is: Provide a reference voltage and safety path for fault currents
Q.122 Which connector is typically used for a high‑definition audio interface (e.g., studio monitors)?
XLR
RJ45
USB‑A
HDMI
Explanation - XLR connectors provide balanced, low‑noise audio connections for professional equipment.
Correct answer is: XLR
Q.123 A connector rated "IP65" offers which level of protection?
Dust‑tight and protected against water jets from any direction
Dust‑tight and protected against temporary immersion
Only dust protection
Only protection against light rain
Explanation - IP65 indicates complete dust protection and resistance to water jets of limited pressure.
Correct answer is: Dust‑tight and protected against water jets from any direction
Q.124 Which connector type is most appropriate for a high‑speed data link between two computers (e.g., 10 Gbps Ethernet)?
M12 X‑coded
RJ45
USB‑A
HDMI
Explanation - M12 X‑coded connectors support up to 10 Gbps Ethernet, making them suitable for high‑speed industrial networking.
Correct answer is: M12 X‑coded
Q.125 The term "insulation displacement connector" (IDC) means that:
The connector requires a soldering process
The connector cuts through insulation to make contact with the conductor
The connector uses a spring mechanism
The connector is waterproof
Explanation - IDC technology pierces the wire’s insulation to create a direct electrical connection without stripping.
Correct answer is: The connector cuts through insulation to make contact with the conductor
Q.126 A connector with a "circular" body, 8‑pin configuration, and a "D‑coded" designation is intended for:
Low‑speed sensor signals
High‑speed Ethernet up to 1 Gbps
Power delivery up to 250 V
Audio applications
Explanation - M12 D‑coded connectors support up to 1 Gbps Ethernet, commonly used in industrial networking.
Correct answer is: High‑speed Ethernet up to 1 Gbps
Q.127 Which connector type is most commonly used for the power cable of a laptop charger?
IEC 60320 C5 (cloverleaf)
RJ45
USB‑C
HDMI
Explanation - The C5 (often called the cloverleaf) is a common three‑pin connector for laptop AC adapters.
Correct answer is: IEC 60320 C5 (cloverleaf)
Q.128 A terminal that is described as "screw‑type, insulated, 2 mm pitch" would typically be used on:
A PCB with tightly spaced terminals for high‑density wiring
A power distribution board handling high current
A low‑voltage wiring harness with large wires
A cable assembly for audio signals
Explanation - 2 mm pitch indicates a compact arrangement suitable for dense PCB layouts.
Correct answer is: A PCB with tightly spaced terminals for high‑density wiring
Q.129 Which connector family is commonly used for industrial fieldbus communication (e.g., PROFIBUS)?
M8
M12
RJ45
USB‑A
Explanation - M12 circular connectors are standard for fieldbus protocols like PROFIBUS and PROFINET.
Correct answer is: M12
Q.130 What does the "IP" in IP rating stand for?
Ingress Protection
International Pin
Insulation Performance
Industrial Power
Explanation - IP stands for Ingress Protection, describing a connector's resistance to solid particles and liquids.
Correct answer is: Ingress Protection
Q.131 Which connector is typically used to connect a PC's graphics card to a monitor for digital video?
HDMI
RJ45
USB‑C
VGA
Explanation - HDMI is widely used for digital video and audio transmission between a graphics card and display.
Correct answer is: HDMI
Q.132 A "shielded" RJ45 connector is primarily used to:
Increase data transfer speed
Prevent water ingress
Reduce electromagnetic interference on Ethernet cables
Support higher voltage
Explanation - Shielded RJ45 connectors provide a conductive path to ground external EMI, improving signal integrity.
Correct answer is: Reduce electromagnetic interference on Ethernet cables
Q.133 Which connector is specified by the IEC 60320 C13 standard?
A three‑pin male power plug used on computer power cords
A six‑pin RJ45 network connector
A USB‑C data connector
A coaxial RF connector
Explanation - IEC C13 is the common female receptacle on computer power cords; its counterpart C14 is the male inlet.
Correct answer is: A three‑pin male power plug used on computer power cords
Q.134 When a connector is rated for "10 kV IEC 60112", it indicates:
The connector can carry 10 kA current
The connector can withstand a 10 kV impulse voltage test per IEC 60112
The connector operates at 10 kHz frequency
The connector can be used in environments up to 10 °C
Explanation - IEC 60112 defines impulse voltage testing; a 10 kV rating shows the connector can endure high voltage transients.
Correct answer is: The connector can withstand a 10 kV impulse voltage test per IEC 60112
Q.135 A terminal block with a "push‑in" design is best suited for:
High‑current power distribution
Quick, tool‑free wiring in prototype boards
Water‑tight sealing
RF signal transmission
Explanation - Push‑in terminals allow wires to be inserted without tools, streamlining prototyping.
Correct answer is: Quick, tool‑free wiring in prototype boards
Q.136 Which of the following is an advantage of using a "cable‑gland" with a connector?
Provides a waterproof seal and strain relief for the cable
Increases the connector’s current rating
Allows for higher data rates
Reduces the connector’s size
Explanation - Cable glands secure and seal the cable at the entry point, protecting against moisture and mechanical stress.
Correct answer is: Provides a waterproof seal and strain relief for the cable
Q.137 A connector that is described as "polarized" ensures:
Higher current capacity
Correct orientation during mating
Reduced electromagnetic emissions
Improved thermal performance
Explanation - Polarization adds asymmetry (keying, notches) to prevent reverse insertion.
Correct answer is: Correct orientation during mating
Q.138 The term "contact plating" in a connector refers to:
The color of the connector housing
A thin metal layer applied to contacts to improve conductivity and corrosion resistance
The mechanical shape of the contact pins
The type of insulation used
Explanation - Plating (e.g., gold, nickel) reduces contact resistance and protects against oxidation.
Correct answer is: A thin metal layer applied to contacts to improve conductivity and corrosion resistance
Q.139 Which connector type is widely used for the audio output of a smartphone?
3.5 mm TRS
RJ45
USB‑C
HDMI
Explanation - The 3.5 mm TRS jack is the standard analog audio output on many smartphones.
Correct answer is: 3.5 mm TRS
Q.140 A connector with a "bayonet" locking system typically requires:
A quarter‑turn twist to lock
A screw to tighten
A push‑in action
A magnetic latch
Explanation - Bayonet connectors lock by aligning pins and twisting to engage a latch.
Correct answer is: A quarter‑turn twist to lock
Q.141 Which connector family is defined by IEC 61076‑2‑109 and is used for high‑temperature sensor connections?
M12
M8
M16
M24
Explanation - IEC 61076‑2‑109 specifies M12 connectors, including variants for high‑temperature environments.
Correct answer is: M12
Q.142 The main purpose of a "fused" connector is to:
Provide EMI shielding
Limit current to protect downstream circuits
Increase mechanical strength
Allow for higher voltage rating
Explanation - Integrated fuses open the circuit when current exceeds a preset value, safeguarding components.
Correct answer is: Limit current to protect downstream circuits
Q.143 Which connector type is most often used for connecting a TV to a set‑top box via HDMI?
HDMI
RCA
VGA
DVI
Explanation - HDMI carries high‑definition audio and video between TV and set‑top boxes.
Correct answer is: HDMI
Q.144 A "keyed" terminal block prevents:
Electrical short circuits
Incorrect wire gauge insertion
Misalignment of the wires
Overheating of the terminal
Explanation - Keyed designs guide wires into the correct slot, reducing wiring errors.
Correct answer is: Misalignment of the wires
Q.145 Which connector is typically used for connecting a PC's Ethernet port to a network switch?
RJ45
USB‑C
HDMI
BNC
Explanation - RJ45 connectors are standard for Ethernet networking cables.
Correct answer is: RJ45
Q.146 A terminal block with a "screw‑type, 5 A rating" is suitable for:
Connecting a high‑power motor
Low‑current signal wiring
Powering a 12 V LED strip drawing 4 A
Connecting a mains AC line
Explanation - The LED strip's current (4 A) is below the terminal’s 5 A rating, making it appropriate.
Correct answer is: Powering a 12 V LED strip drawing 4 A
Q.147 Which connector is widely used for the data interface of a solid‑state drive (SSD) in modern computers?
SATA
PCIe‑M.2
USB‑A
RJ45
Explanation - M.2 (NGFF) connectors provide PCIe lanes for high‑speed SSDs in laptops and desktops.
Correct answer is: PCIe‑M.2
Q.148 A connector rated as "IP44" offers protection against:
Dust ingress and water jets from any direction
Dust ingress only
Water immersion up to 1 m
No protection against water
Explanation - IP44 means the connector is protected against solid objects larger than 1 mm and water splashing from any direction.
Correct answer is: Dust ingress and water jets from any direction
Q.149 Which connector type is commonly used for a PC's USB ports?
USB‑C
RJ45
HDMI
BNC
Explanation - USB‑C is increasingly used for data, video, and power delivery on modern PCs.
Correct answer is: USB‑C
Q.150 The main advantage of a "circular" connector over a rectangular one in harsh environments is:
Higher data rate
Better sealing and resistance to vibration
Lower cost
Simpler wiring
Explanation - Circular connectors often feature robust sealing and latch mechanisms, making them suitable for rugged applications.
Correct answer is: Better sealing and resistance to vibration
Q.151 In a connector datasheet, "Operating Temperature" is listed as "-40 °C to +85 °C". This indicates:
The connector can be stored at those temperatures
The connector can operate safely within that temperature range
The connector will melt outside that range
The connector is waterproof
Explanation - Operating temperature defines the range in which the connector maintains its performance specifications.
Correct answer is: The connector can operate safely within that temperature range
Q.152 A terminal that is described as "screw‑type, insulated, 2 mm pitch" would typically be mounted on:
A high‑current power board
A dense PCB with close‑spaced terminals
A low‑voltage cable harness
An audio amplifier chassis
Explanation - 2 mm pitch indicates a compact arrangement suitable for high‑density PCB layouts.
Correct answer is: A dense PCB with close‑spaced terminals
Q.153 Which connector family is specified by IEC 60320 C5 and commonly called "cloverleaf"?
Power connector for laptop AC adapters
Ethernet connector
Audio jack
Coaxial RF connector
Explanation - IEC C5 (cloverleaf) is a three‑pin AC power connector used for many laptop chargers.
Correct answer is: Power connector for laptop AC adapters
Q.154 A connector with a "twist‑lock" mechanism is most likely to be found in:
Consumer audio equipment
Industrial sensor wiring
Desktop computer USB ports
Smartphone chargers
Explanation - Twist‑lock connectors provide a secure, vibration‑resistant connection common in industrial applications.
Correct answer is: Industrial sensor wiring