1. The problem statement, all variables and given/known data Two crates rests on the floor, one next to the other. A man pushes with a horizontal force of 400 N on the larger (50.0 kg) crate, which, in turn, pushes the other (25.0 kg) so that both slide as he walks along. Each crate experiences a friction force opposing the motion equal to 40% of its weight. 1.Determine the acceleration of the crates. Answer in m/s^2 2.What is the force exerted by one crate on the other? Answer in Newtons 2. Relevant equations and 3. The attempt at a solution 1) total friction force Ff = 40 x (50+25) x 9.8/100 = 294 N =>F(net) = F(applied) - Ff =>F(net) = 400 - 294 = 106 N =>By F = ma =>106 = 75 x a =>a = 106/75 = 1.41 m/s^2 => CORRECT 2)F(net) = 106 N => INCORRECT. Why? Please help!!!