Click on the reset button, and stack one 50kg. crate on top of the other, so that the total mass is 100kg. The Friction should be set to halfway between None and Lots. Adjust the Applied Force (force exerted) slowly, and determine when the crates begin accelerating. What is the minimum force that must be exerted on the crates so that they accelerate?

490.5 N

Explanation:

Coefficient of friction is 0.5 since friction force is set to halfway between none and lots. Minimum force is given by multiplying the weight and coefficient of friction

F= kN where k is coefficient of friction while N is weight. Also, N=mg where m is mass and g is acceleration due to gravity.

F=kmg=0.5*100*9.81=490.5 N

im sorry i dont know