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Ryo124
Oct25-07, 11:55 AM
1. The problem statement, all variables and given/known data

A man pushes a heavy box. The mass of the box is 100kg. There is friction between the man and the floor; the frictional force is 150N. As the mas pushes hard, the box accelerates with acceleration 0.3m/s/s. Calculate the force F exerted by the man on the box.

2. Relevant equations

F = ma

3. The attempt at a solution

Does the man need to at least exert 150N to overcome the force of friction? I don't know how to attempt the problem.

Doc Al
Oct25-07, 12:15 PM
Does the man need to at least exert 150N to overcome the force of friction?
Absolutely. If you drew a diagram of the situation (always a good idea), what horizontal forces would you show acting on the box? Apply Newton's 2nd law to the box.

Ryo124
Oct25-07, 02:00 PM
So the answer would be 180N, correct?

Doc Al
Oct25-07, 03:52 PM
Correct.