In the figure, a uniform plank, with a length L of 4.75 m and a weight of 630 N, rests on the ground and against a frictionless roller at the top of a wall of height h = 2.36 m. The plank remains in equilibrium for any value of θ = 70.0∘ or more, but slips if θ < 70.0∘. Find the coefficient of static friction between the plank and the ground.
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In the figure, a uniform plank, with a length L of 4.75 m and a weight of 630 N, rests on the ground and against a frictionless roller at the top of a wall of height h = 2.36 m. The plank remains in equilibrium for any value of θ = 70.0∘ or more, but slips if θ < 70.0∘. Find the coefficient of static friction between the plank and the ground.
