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Toranc3
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Homework Statement
A small box of mass 1 is sitting on a board of mass 2 and length L . The board rests on a frictionless horizontal surface. The coefficient of static friction between the board and the box is Us . The coefficient of kinetic friction between the board and the box is, as usual, less than Us.
Find the constant force with the least magnitude that must be applied to the board in order to pull the board out from under the the box (which will then fall off of the opposite end of the board).
Homework Equations
F=ma
The Attempt at a Solution
I have a couple of questions:
1. The acceleration does not go to 0 in the x direction because the board is pulled with a constant force and therefore a constant acceleration because force and acceleration are both constant. Is this right? Or do they go to zero because they were at rest?(Inertia, Newton's first law)
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