A ball is dropped from some height. It bounces off the floor and rebounds with a speed that is one-half the speed it had just before it struck the floor. How high will the ball rise compared to the height from which it was dropped

The correct option is C

Explanation:

According to third equation of motion, v

2

=u

2

+2ax

Here, u=0 m/s

a=−g and x=−h

Negative sign indicates downward direction. Displacement and acceleration both are downwards.

So,v=±

2(−g)(−h)

We take minus sign because it is downwards.

v=−

2gh

After bouncing. velocity becomes 80% of v, i.e.,

v

′

=+0.8

2gh

(positive sign because the direction of ball has reversed after bouncing and is upwards.

Applying third equation of motion again, for u=v

′

, v=0 and a=−g

v

2

=u

2

+2×a×x

Thus,

0=0.64(2gh)+2(−g)x

or

x=0.64h

wavelegth as in spectrum red oygbiv

energy can be converted from one form to another, but it cannot be created or destroyed in ordinary chemical or physical means. do not understand what you are asking but hope this