Question

A body is dropped from a height of 2m.it penetrate into sand on the ground through a distance of 10 cm before it come to rest. what is the retardardation of body in the sand.

Answer 1

I think the answer is
$-100m {s}^{ - 2}$
how?→
first find the velocity the ball would have when it just touch the ground i.e.,
by using, v=√2gh which comes out to be 2√10m/s.
now, find the retardation the ball experienced using,
${v}^{2} - u ^{2} = - 2as$
which comes out to be the above written answer...
hope it helped