USPS 955 TEST
Ohm's law formula - ANSWER-V = IR
HMI (Human Machine Interface) - ANSWER-A PLC device that
provides means of automated systems and people's interaction
with the PLC control system.
lever - ANSWER-Simple machine that provides a mechanical
advantage in carrying loads
fulcrum - ANSWER-Hinge point for the lever
input force - ANSWER-The effort that converts into output force
output force - ANSWER-The output force carries the load in a
lever
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1st class lever - ANSWER-fulcrum is located between the input
and output forces
Torque - ANSWER-a force that causes rotation
2nd class lever - ANSWER-fulcrum at the end, load in the
middle; wheel barrow, car-jack
3rd class lever - ANSWER-fulcrum at the end, effort in the
middle; tweezers, baseball bat
gear - ANSWER-A wheel with equally sized and spaced teeth
located on its circumference
circumference - ANSWER-The distance around a circle
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Gear Ratio Formula - ANSWER-Number of teeth in wheel
1/number of teeth in wheel 2 = Velocity of wheel 2/velocity of
wheel 1
Pulley - ANSWER-A simple machine that consists of a grooved
wheel with a rope or cable wrapped around it.
fixed pulley - ANSWER-A pulley that is attached to a structure
moveable pulley - ANSWER-A pully that is directly attached to
the load. Provides a mechanical advantage by dividing the
weight between the part of the rope connected to the ceiling
and the part that is pulled.
Applied force formula - ANSWER-F=W/N (Number of ropes)
Length of rope pulled formula - ANSWER-L= vertical distance
of the load lifted (D)/Number of Load supporting ropes (N)
spring - ANSWER-Object used to store mechanical energy
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Hooke's Law Formula - ANSWER-F = kx (spring constant x
extension)
Incline Plane - ANSWER-A flat supporting surface tilted on an
angle, used to help raise or lower a load with less work
wedge - ANSWER-A compound tool that is triangular in shape.
Can be used to seperate two objects or portions of an object,
lift an object, or hold an object in place.
Screw - ANSWER-Converts rotational motion into linear motion
and a torque to a linear force.
centrifugal force - ANSWER-Outward force that draws a
rotating body away from the center of rotation. Opposite
direction to the center of the circle