Problem 5-108 Force and Kinematics

Tiny Tompfind, a man of mass \(72\; kg\), jumps (from rest) from a table \(92 \;cm\) to the floor below. As he lands, he bends his knees so that he decelerates over a distance of \(35 \;cm\).

(a) What is Tiny's speed just as he hits the floor?
(b) As he decelerates, what is the magnitude of the force exerted on him by the floor?

As always we must choose a coordinate system in which to solve the problem. Which is best?

Four possible coordinate systems for Tiny Tompfind jumping.

(A)

(B)

(C)

(D)