Energy Concepts

Question 1

Equations for work done

Answer 1

Change in KE
Force x distance
Fx X x costheta

Question 2

Equation for up hill / down hill work done

Answer 2

+/- mgh -frxd=1/2mv^2-1/2mu^2

Question 3

Conservation of energy

Answer 3

Energy cannot be created or destroyed it can only be changed from one form to another

Question 4

Elastic potential energy

Answer 4

Change in pe =1/2kx^2

Question 5

Definition of gravitational potential energy

Answer 5

is the energy possessed by an object due to its position or height above the earth.

Question 6

Elastic potential energy stored in a wire

Answer 6

1/2 x F x X

Question 7

Force equation with force and extension

Answer 7

Force=K x X

Question 8

Definition of power

Answer 8

Power is the rate of doing work , it is a scalar quantity and is measured in Watts or Joules per second

Question 9

Equation for power

Answer 9

Power=energy/time
Power=force x velocity

Question 10

Define watt

Answer 10

1 watt is the rate of work done on an object or the rate of energy transfer of 1joule per 1 second

Question 11

Efficiency equations

Answer 11

useful energy output/total energy input x 100
useful power output/total power input x100