Exercise

For work to be performed, energy must be:

Joule is the unit of:

Which of the forces involved in dragging a heavy object on a smooth, horizontal surface, have the same magnitude?

Power is a measure of the:

While dragging or lifting an object, negative work is done by:

The potential energy of your body is least when you are _____.

(Choose from: sitting on a chair, sitting on the ground, sleeping on the ground, standing on the ground)

The total energy of an object falling freely towards the ground _____.

(Choose from: decreases, remains unchanged, increases, increases in the beginning and then decreases)

If we increase the velocity of a car moving on a flat surface to four times its original speed, its potential energy _____.

(Choose from: will be twice its original energy, will not change, will be $4$ times its original energy, will be $16$ times its original energy)