Question

A raw egg can be dropped from a third-floor window and land on a foam-rubber pad on the ground without breaking.
If a 75.0-g egg is dropped from a window located 32.0m above the ground and a foam-rubber pad that is 15.0cm thick stops the egg in 9.20ms.
(a) By how much is the pad compressed?
(b) What is the average force exerted on the egg after it strikes the pad?
Note: Assume constant upward acceleration as the egg compresses the foam-rubber pad.

Answer 1

A)

That acceleration can then be plugged in to yet another kinematic so find how far the pad was compressed!

\[d=v_it-\frac{1}{2}at^2\]
(at should be less than 15cm! ^_^)

B) To find the average force the egg exerted, you can set up a free body diagram on the egg as it his the pad


Then sum the forces, knowing that the net acceleration is the acceleration you found in part a

\[ \sum F = F_{pad}-mg=ma\]
\[F_{pad} = m(a+g)\]