19 terms

# Hug PHPS CIA Chapter 15

Energy Transformations
###### PLAY
energy
the capacity of a physical system to do work
kinetic energy
energy of motion; KE=1/2 mv²
potential energy
stored energy;
gravitational potential energy
potential energy that depends on the height of an object PE=mgh, mass times acceleration due to gravity, times the height of the object.
elastic potential energy
potential energy that is stored when a body is deformed (for example a coiled spring or stretched rubber band)
mechanical energy
kinetic or potential energy associated with the motion or position of an object
thermal energy
the total kinetic and potential energy of all the particles in a substance; particles with greater temperatures have more kinetic energy.
chemical energy
potential energy stored in chemical bonds of molecules.
electrical energy
the energy of electrically charged particles moving from one place to another
electromagnetic energy
A form of energy that travels through space as waves; example light, microwaves, x-rays.
nuclear energy
The energy released by a nuclear reaction; The nucleus of certain atoms may release energy due to fusion or fission.
energy transformations
A change from one form of energy to another
law of conservation of energy
The fundamental principle of physics that the total energy of an isolated system is constant despite internal changes. "Energy can neither be created or lost."
fossil fuels
Coal, oil, natural gas, and other fuels that are ancient remains of plants and animals; nonrenewable energy resources.
energy conservation
The practice of finding ways to use less energy or to use energy more efficiently.
E = mc²
Energy and mass are equivalent and can be converted into one another; Einstein's equation.
work
The transfer of energy from one physical system to another expressed as the product of a force and the distance through which it moves a body in the direction of that force; "work equals force times distance"; W=FxD
friction
The force that opposes the motion of one surface as it moves across another surface. This can be static, sliding or rolling friction. Friction is dependent upon the surface slid against and the mass that is sliding.
coefficient of friction
the ratio of the force of friction to the normal force acting between two objects. The Greek letter mu represents this coefficient. The rougher the surface the greater the mu.