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After calling a wall of 3 m heigh a mass...

After calling a wall of `3 m` heigh a mass of weight W drops himself to the ground. If his body comes to a complete stop in `0.15 s`. After his feet touch the ground, calculate the average impulsive force in the vertical direction exerted by ground on his feet.

A

`5W`

B

`5.21W`

C

`3W`

D

`6W`

Text Solution

Verified by Experts

The correct Answer is:
B
Velcoity before strike
`u = sqrt(2gh)`
Impulse `F Deltat = m(v - u)`
`rArr F = (m(v - u))/(t) = (w (0 - sqrt(2gh)))/(g xx 0.15) = 5.21 W`
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