Energy Transferred

Whenever an object is moved, work is said to be done. To make an object move, a force has to be put into it and that force requires energy. So in simple terms...

Work Done = Energy Transferred (to move the object).

 

We can calculate the work done if we know the force moved and the distance it has been moved over. We can use the equation...

 

So if we use a force of 20N to move a crate 5m across a room, then we can calculate the work done (or the energy transferred) by using the equation...

Work Done = 20N (Force) x 5m (Distance) = 100J

So the energy used would be 100 Joules.

 

Kinetic Energy

Kinetic Energy means movement energy. To calculate the movement energy we would need to know two facts - firstly the velocity of the object and secondly the mass of the object. We can measure the amount of kinetic energy by using the following equation...

So we could work out the kinetic energy of a 500kg car travelling at 12 m/s using the above equation...

Kinetic Energy = ½ x 500 x 12² = 36,000J

 

As a summary of this, try these podcasts from BBC bitesize...

Click the logo above for an audio podcast.