work and machines Flashcards
the action that results when a force causes an object to move in the same direction in which the force is applied
work
a device that helps make work easier by changing the size/direction of a force
machine
amount of work put into a machine
work input
amount of work that comes out of a machine
work output
work output can never be ________ than work input
larger
a number that tells how many times a machine multiplies the input force
mechanical advantage
a percentage comparison of a machine’s work output with its work input
mechanical efficiency
a simple machine that is a flat, slanted surface
inclined place
a simple machine that is a double inclined plane that moves
wedge
a simple machine that is an inclined plane wrapped in a spiral
screw
a simple machine consisting of a bar that pivots at a fixed point called the fulcrum
lever
fulcrum is balanced between input force and output force
first class lever
output force is balanced between fulcrum and input force
second class lever
input force is between fulcrum and output force
third class lever
a simple machine consisting of two circular objects of different sizes that rotate around the same point
wheel and axle
the wheel is always ______ than the axle
bigger
a simple machine that consists of a grooved wheel that holds a rope or cable
pulley
does not move, does not increase force, changes direction, and has a mechanical advantage of one
fixed pulley
moves with the load, increases force, does not change direction, and the mechanical advantage can be calculated by adding up the number of line segments supporting the load
moveable pulley
combination of two or more simple machines
compound machine
the rate at which work is done
power
