A physics 211 student is trying to pull a box of books of mass m = 40 kg across the floor as shown in the figure. The coefficient of static friction is μs.

If the angle θ = 36.9° and the coefficient of friction μs = 0.3, what is the minimum tension, T, required to get the box moving?

Question

A physics 211 student is trying to pull a box of books of mass m = 40 kg across the floor as shown in the figure. The coefficient of static friction is μs.

If the angle θ = 36.9° and the coefficient of friction μs = 0.3, what is the minimum tension, T, required to get the box moving?

anonymous · Answer

Draw a picture with the Force that pulls it forward = Tcos(theta) The force going in the opposite direction is the force due to friction. Set those two forces equal to each other and solve for T.