Question

A 55 kg pole vaulter falls from rest from a height of 5.4 m onto a foam rubber pad. The pole vaulter comes to rest 0.24 s after landing on the pad.
a. Calculate the athlete's velocity just before reaching the pad
b. Calculate the constant force exerted on the pole vaulter due to the collision.

Answer 1

Answer:

a) 10.3 m/s

b) 566 N

Explanation:

$v {}^{2} = {u}^{2} + 2as \\ v {}^{2} = 0 {}^{2} + 2(9.81)(5.4) \\ v = 10.3 \: ms {}^{ - 1}$

$force \: = \frac{d(mv)}{dt} \\ = 55(10.293) \\ = 566 \: newtons$