(adsbygoogle = window.adsbygoogle || []).push({}); 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 equationsand3. 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!!!

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# Homework Help: What is the force exerted by one crate on the other?

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