P2- work, energy and momentum

energy and work

• when a force moves an object, work is done
• work done is equal to energy transferred
• work= force x distance
• work done to over come friction is transferred into energy by heating, the objects rub together to form heat that heats them and the surroundings e.g. the fricition between brake pads

gravitational potential energy

• it is the energy stored in an object because of its position in the earths gravatational field, whhenever an object is moved vertically upwards it gains GPE equal to the work done by the lifting force
• change in gravitationl potential energy= mass x field strength x height
• power is the rate of transfer of energy
• power= energy / time

kintetic energy

• kinetic energy depends on its mass and speed
• greater the mass and faster the speed= more kinetic energy
• kinetic energy= 1/2 x mass x speed2

momentum

• the greater the mass and velocity of an object the greater the momentum
• momentum=…