Question

a marble ball of mass 1kg falls from the top of the building of height 10 m and penetrate 0.5 m deep into the sand.calculate the average resistance offered by the sand and the time taken by the ball to penetrate?​

Answer 1

Explanation:

m = 5 kg

h = 50 m

velocity = v just before hitting the ground

v² = u² + 2 g h = 0 + 2 * 9.8 * 50 = 980

When the stone is penetrating the sand:

v² = u² + 2 a s

0 = 980 + 2 * a * 1

a = - 490 m/s²

Average resistance Force offered by sand = m a = - 5 * 490

=- 2, 450 N