Ch 6 Energy# Flashcards
State the 6 types of energy stores
1) Elastic potential
2) chemical potential
3) gravitational potential
4) kinetic
5) nuclear
6) internal
State 1 way how energy is transferred.
There are a total of 5 ways.
Energy can be transferred:
1) mechanically by a force over a distance
2) by heating due to a temperature difference.
3) by the propogation of electromagmetic wave
4) by the propogation of electromagmetic wave
5) by the propogation of sound wave
Define work done.
Work done is the energy transferred to or from an object through the application of force along a distance in a straight line.
Formula for work done
Work done = force x distance moved in the straight line (W = F x d)
Not to be confused with moments in Chapter Turning Effect of Force
What is the SI unit for work done?
joule (J)
Note that work done has the same SI unit as energy.
Define energy.
Energy is the ability to do work.
What is kinetic energy?
Energy associated with the motion of a body.
i.e. all moving bodies will have KE.
Formula for kinetic energy.
KE = 0.5mv2
What is gravitational potential energy?
Energy associated with the position of a body in a gravitational field.
i.e. all bodies above the ground will have GPE.
Formula for gravitational potential energy.
GPE = mgh
What is the principle of conservation of energy?
3 points:
1. The principle of conservation of energy states that energy can neither be created nor destroyed.
2. Energy can only be transferred from one store to another.
3. The total energy in an isolated system is constant.
Define power.
Power is the rate of doing work.
Power is how fast energy is being converted from one form to another
Formula for power
power = work done / time (P = W/t) power = energy change / time (P = E/t)
