If you lift a 20N box of toys to the top shelf of a closet that is 3 m high, how much gravitational potential energy will the box have?

60 J

Explanation:

Potential Energy: This can be defined as the energy possessed by a body, due to its position. The S.I unit of potential energy is Joules. The Formula of potential energy is given as

Ep = mgh or

Ep = Wh Equation 1

Where Ep = Potential energy of the box, W = Weight of the box, h = Height.

Given: W = 20 N, h = 3 m.

Substitute into equation 1

Ep = 20×3

Ep = 60 J.

Hence the gravitational potential energy of the box = 60 J

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