Work and Power
It is the rate at which work is done
Power
They help to make work easier
Machines
A combination of two or more simple machines
Compound machine
It is the energy of stretched things
Elastic potential energy
The transfer of energy
Work
It is the unit of work
Joule
The force you exert on a machine
Input force
It is an inclined plane wrapped around a cylinder.
A screw
It is the sum of kinetic and potential energy
Mechanical energy
An open system
Exchanges energy and matter with it's environment
Work is only done when...
Force is parallel to motion and displacement happens
Output force divided by input force =
mechanical advantage
A machine whose fulcrum is between the input and output forces
A lever
It says that energy is never created or destroyed
law of conservation of energy
The ability to do work
Energy
Are the units of power
Watts
What is the formula for mechanical efficiency?
(Output work / input work) X 100%
Type of machine used to raise curtains and flags
A pulley
Friction causes waste in the form of
thermal energy
GPE is what and how to you calculate it
Gravitational Potential Energy = mass * height * gravity
power = (energy)/(?)
? =
time
Machines change the ____ and _____ of a force
Magnitude and direction
The six types of simple machines are
lever, pulley, wheel and axel, incline plane, screw, and wedge
You increase GPE of an object by ____
Increasing it's height
What is the formula for kinetic energy?
1/2MV2