Question

Example 2. A ball is thrown down from a height of 10 m with an initial velocity u. The ball after striking the ground rises to same height because 50% of energy of the ball is wasted in striking with the ground. Calculate the value of u. (g = 9.8 ms ?). If the initial velocity of ball u be upwards, to what height would the ball have risen after striking the ground ? ​

Answer 1

Answer:

14 ms

Explanation:

Correct option is

14ms

Initial total energy at height h is, =21mu2+mgh

Energy of ball after collision, 

                                    =50% of total energy.

As ball rebounds to same height h, then

mgh= 50% 0f total energy.

         =41mu2+21mgh

therefore,                u=sqrt(2gh)=14m/s