Question

1. A ball of mass m is dropped from a height H above a level floor as shown in figure. After striking the ground it bounces off back and reaches up to height h. Based on above information, answer the following questions: H W​

Answer 1

Answer:

The correct option is C

√

2

g

h

Mass of the ball = m

height = h

Potential energy at height h, (P.E.) = mgh

Kinetic enercy just before hitting the ground (K.E.)

=

1

2

m

v

2

P.E. become zero just before hitting the ground.

Hence This P.E. converted into K.E. ,

So both must be equal P.E. = K.E.

m

g

h

=

1

2

m

v

2

v

2

=

2

g

h

v

=

√

2

g

h