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Homework Statement
A 2.5 kg block is initially at rest on a horizontal surface. A horizontal force
(a) Determine the magnitude of the frictional force acting on the block if the magnitude of
Homework Equations
F_friction = Mu*F_normal
The Attempt at a Solution
I really need help with this one, because I don't understand why I get a wrong answer.
Firstly, the net force in the y direction is 0. So F_g = P + F_N.
Then F_N = F_g  P = 2.5 * 9.8  8 = 16.5 N
Then since (I believe) the block is stationary, we use μs = 0.43, and so F_f = 0.43 * 16.5 =7.095.
Satisfied with my answer, I put this in the webassign, but it won't accept this as the correct answer. Where did I go wrong?
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