Question

A ball of mass 50 gram is made to fall from a height of 20m. it hits the ground and loses 25% of its energy and rebounce . calculate the height attained by the object​

Answer 1

Answer:

2.5m from the groud

Explanation:

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Answer 2

Given:-

→ Mass of the ball = 50g

→ Height from which it is dropped = 20m

→ Percentage of loss of energy of the

body, when it hits the ground = 25%

To find:-

→ Height attained by the ball after

rebouncing.

Solution:-

Firstly, let's convert the mass of the body from g to kg.

=> 1 g = 0.001kg

=> 50g = 50(0.001)

=> 0.05 kg

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Let the required height be hբ and the height from which the ball is dropped be hᵢ .

We know that :-

P.E. = mgh

Where :-

• P.E is energy possessed by the

body [potential].

• m is mass of the body.

• g is acceleartion due to gravity.

• h is height

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Now, it is given that the energy of the ball reduces by 25% . It means that the energy possessed by the ball is (100-25) = 75%

=> mghբ = 75% of mghᵢ

=> 0.05 × g × hբ = 0.75 × 0.05 × g × 20

=> hբ = 0.75 × 20

=> hբ = 15m

Thus, height attained by the ball after rebouncing is 15m .