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Question
A body of mass 37 kg rests on a rough horizontal surface. The minimum horizontal force required to just start the motion is 68.5 N. In order to keep the body moving with constant velocity, a force of 43 N is needed. What is the value of coefficient of static friction?
Solution
Given: FL = 68.5 N, Fk = 43 N, m = 37 kg, g = 9.8 m/s2
To find: Coefficient of static friction (μS)
Formula: μS = `("F"_"L")/"N" = ("F"_"L")/"mg"`
Calculation:
From formula,
∴ `mu_"s" = "F"_"s"/"N"`
= 68.5/(37 xx 9.8)`
= 0.1889
∴ The coefficient of static friction is 0.1889.
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