A 40.6-kg crate rests on a horizontal floor, and a 69.1-kg person is standing on the crate. Determine the magnitude of the normal force that (a) the floor exerts on the crate and (b) the crate exerts on the person.

Answer 1

a. F = (m1+m2)g,
F = (40.6+69.1)*9.8 = 1075N.

b. F = -1075N.

Answer 2

A 110- crate, starting from rest, is pulled across a floor with a constant horizontal force of 380 . For the first 11 the floor is frictionless, and for the next 11 the coefficient of friction is 0.33.What is the final speed of the crate?