Question

a ball of mass 20g falls from a height of 10m and after striking the ground it rebounds from the ground to a height of 8m​

Answer 1

Answer:

answer a1

k.e before striking v=✓2gh( by using v^2= u^2+ 2as)

v= ✓2×10×10

k.e =1/2 mv^2

1/2 ×0.02×200

k.e 2 joules

1. loss in kinetic energy

mgh1 - mgh2/mgh1

2/10

20%

Answer 2

The ball falls vertically downward.

Mass of the ball=m=20g=0.02kg

Height from which it falls=h₁=10m

acceleration due to gravity=g=10m/s²

so, P.E₁=mɡh₁=0.02×10×10=2J

Now, P.E—> K.E.

So, P.E= K.E

Hence K.E= 2J

Bro please tell me from which book this question is?