What is the energy of a 4 kg apple that is sitting on a 2 m high tree branch?

The correct answer to the question is: 78.4 J

EXPLANATION:

As per the question, the mass of the apple is given as m = 4Kg.

The apple is present at a height of 2 m from the ground.

Hence, height of the apple h = 2 m.

We are asked to calculate the energy possessed by the apple.

The energy of the apple is nothing else than the gravitational potential energy of the apple.

The gravitational potential energy of a body at a height h is calculated as -  

Gravitational potential energy P.E = mgh

Here, m is the mass of the body.

         g is known as acceleration due to gravity and it's value is g =  9.8 m/c2

The potential energy of the apple is calculated as-

                                   P.E = m × g× h

                                         = 4 × 9.8 × 2 Joule

                                         = 78.4 J       ( Ans )

Hence, the energy of apple is 78.4 J.

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