Posted by **Anonymous** on Thursday, February 3, 2011 at 12:42pm.

A boy weighing 4.2 102 N jumps from a height of 1.80 m to the ground below. Assume that the force of the ground on his feet is constant.

(a) Compute the force of the ground on his feet if he jumps stiff-legged, the ground compresses 2.20 cm, and the compression of tissue and bones is negligible.

(b) Compute the force his legs exert on his upper body (trunk, arms, and head), which weighs 2.50 102 N, under the conditions assumed above.

(c) Now suppose that his knees bend on impact, so that his trunk moves downward 44.0 cm during deceleration. Compute the force his legs exert on his upper body.

## Answer this Question

## Related Questions

physics - an 80 kg boy holding on to a helium balloon jumps off of a 20m tall ...

physics - a rock weighing 20.0N falls from a height of 16.0m and sinks 0.600 m ...

Physics - An athlete with a mass of 62 kg jumps and lands on the ground on his ...

Physics - A boy starts at rest and slides down a frictionless slide as in the ...

physics - A student (m = 68 kg) falls freely from rest and strikes the ground. ...

Physics - A student (m = 63 kg) falls freely from rest and strikes the ground. ...

PHYSICS - A student (m = 63 kg) falls freely from rest and strikes the ground. ...

Tough Math - Suppose the ball was 3.24 feet above ground when it was hit, and ...

Physics 11U - At the moment when a shot putter releases a 5.00 kg shot, the shot...

Math - Can you please help me with a math problem Suppose the ball was 3.24 feet...