USPS EXAM 955 QUESTIONS WITH
COMPLETE ANSWERS
What is an idler gear used for? - ANSWER-To change direction of spin
What mechanical device can be used to create oscillating motion? - ANSWER-CAM
Potential energy is - ANSWER-stored energy
Electricity is the flow of what? - ANSWER-electrons
What is the measuring unit name of current? - ANSWER-Ampere
What are the formulas for Ohm's law? - ANSWER-V=IR, I=V/R, R=V/I
A capacitor blocks and passes what? - ANSWER-Blocks DC and passes AC
An electrical magnetic device which pulls in a plunger is called what? - ANSWER-
solenoid
What device converts electrical energy into mechanical energy? - ANSWER-motor
What device converts mechanical energy into electrical energy? - ANSWER-
generator
A __________ converts one type of energy to another. - ANSWER-Transducer
What type of current is commonly applied to a transformer? - ANSWER-AC
Why is a capacitor used across the contacts of a relay? - ANSWER-To prevent
arching
Why is a diode used across the coil of a relay? - ANSWER-Prevents de-energizing
coil voltage from being reintroduced into the line
When installing an electrolytic capacitor in a circuit, what precaution must be
observed? - ANSWER-polarity
Current in a series circuit at any given point is? - ANSWER-same
How many paths must current travel in a parallel circuit? - ANSWER-2 or more
How much resistance is in a short circuit? - ANSWER-0 Ohms
Name the leads on a transistor? - ANSWER-base, collector, emitter
How many leads does a MOSFET have? - ANSWER-3
, Name the leads in a MOSFET? - ANSWER-Gate, Source, Drain
What type of fire extinguisher is used on electrical fires? - ANSWER-C, BC, ABC
Why is it bad to mix cleaning chemicals? - ANSWER-Can produce a poisonous gas
What factors should be considered when erecting a ladder? - ANSWER-Height of
the job, the distance the ladder is from the wall, type of job, and capacity
How far out should the bottom of a ladder go for each foot up? - ANSWER-1/4
Who may remove a lockout? - ANSWER-The person who put it there
Who is responsible for safety? - ANSWER-Each individual
Why should you never bridge a fuse with copper wire, a bullet or other material? -
ANSWER-A major safety hazard to you and equipment
While working on a circuit and you are not near the circuit breaker box, what should
be done? - ANSWER-Lock out and tag out equipment
If 200ftlbs of work is expanded to lift 20 lbs on to a 10 foot platform, how much is
required if a 20 foot ramp is used? - ANSWER-200ftlbs
Mechanical Power is defined as - ANSWER-Force times distance divided by time
Pulleys never touch in a belt and pulley configuration. - ANSWER-True
Work can be defined as - ANSWER-Kinetic Energy
Define Energy - ANSWER-The ability to do work
Why would a stethoscope be used on a conveyor system? - ANSWER-Listen for bad
bearings
What tool is best suited to remove debris from a grind stone? - ANSWER-Dressing
Tool
What tool is normally used to punch holes in sheet metal? - ANSWER-Metal Punch
What is a counter sink bit use for? - ANSWER-Used to make a recess, cone shaped
holes and counter sink screws
What is the best tool for resurfacing the face of a chisel? - ANSWER-Grinder
What is used to remove the rough edge of a freshly cut pipe? - ANSWER-Reamer
What tool is used to remove the head of a rivet? - ANSWER-Metal Chisel
COMPLETE ANSWERS
What is an idler gear used for? - ANSWER-To change direction of spin
What mechanical device can be used to create oscillating motion? - ANSWER-CAM
Potential energy is - ANSWER-stored energy
Electricity is the flow of what? - ANSWER-electrons
What is the measuring unit name of current? - ANSWER-Ampere
What are the formulas for Ohm's law? - ANSWER-V=IR, I=V/R, R=V/I
A capacitor blocks and passes what? - ANSWER-Blocks DC and passes AC
An electrical magnetic device which pulls in a plunger is called what? - ANSWER-
solenoid
What device converts electrical energy into mechanical energy? - ANSWER-motor
What device converts mechanical energy into electrical energy? - ANSWER-
generator
A __________ converts one type of energy to another. - ANSWER-Transducer
What type of current is commonly applied to a transformer? - ANSWER-AC
Why is a capacitor used across the contacts of a relay? - ANSWER-To prevent
arching
Why is a diode used across the coil of a relay? - ANSWER-Prevents de-energizing
coil voltage from being reintroduced into the line
When installing an electrolytic capacitor in a circuit, what precaution must be
observed? - ANSWER-polarity
Current in a series circuit at any given point is? - ANSWER-same
How many paths must current travel in a parallel circuit? - ANSWER-2 or more
How much resistance is in a short circuit? - ANSWER-0 Ohms
Name the leads on a transistor? - ANSWER-base, collector, emitter
How many leads does a MOSFET have? - ANSWER-3
, Name the leads in a MOSFET? - ANSWER-Gate, Source, Drain
What type of fire extinguisher is used on electrical fires? - ANSWER-C, BC, ABC
Why is it bad to mix cleaning chemicals? - ANSWER-Can produce a poisonous gas
What factors should be considered when erecting a ladder? - ANSWER-Height of
the job, the distance the ladder is from the wall, type of job, and capacity
How far out should the bottom of a ladder go for each foot up? - ANSWER-1/4
Who may remove a lockout? - ANSWER-The person who put it there
Who is responsible for safety? - ANSWER-Each individual
Why should you never bridge a fuse with copper wire, a bullet or other material? -
ANSWER-A major safety hazard to you and equipment
While working on a circuit and you are not near the circuit breaker box, what should
be done? - ANSWER-Lock out and tag out equipment
If 200ftlbs of work is expanded to lift 20 lbs on to a 10 foot platform, how much is
required if a 20 foot ramp is used? - ANSWER-200ftlbs
Mechanical Power is defined as - ANSWER-Force times distance divided by time
Pulleys never touch in a belt and pulley configuration. - ANSWER-True
Work can be defined as - ANSWER-Kinetic Energy
Define Energy - ANSWER-The ability to do work
Why would a stethoscope be used on a conveyor system? - ANSWER-Listen for bad
bearings
What tool is best suited to remove debris from a grind stone? - ANSWER-Dressing
Tool
What tool is normally used to punch holes in sheet metal? - ANSWER-Metal Punch
What is a counter sink bit use for? - ANSWER-Used to make a recess, cone shaped
holes and counter sink screws
What is the best tool for resurfacing the face of a chisel? - ANSWER-Grinder
What is used to remove the rough edge of a freshly cut pipe? - ANSWER-Reamer
What tool is used to remove the head of a rivet? - ANSWER-Metal Chisel
