Concept explainers
A block of mass m is at rest at the origin at t = 0. It is pushed with constant force F0from x = 0 to x = L across a horizontal surface whose coefficient of kinetic friction is µk= µ0(1 −x/L). That is, the coefficient of friction decreases from µ0at x = 0 to zero at x = L
a. Use what you've learned in calculus to prove that
b. Find an expression for the block's speed as it reaches position L.
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Physics for Scientists and Engineers: A Strategic Approach, Vol. 1 (Chs 1-21) (4th Edition)
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