Q: The force required to just move a body up the inclined plane is double the force required to just prevent the body from sliding down the plane. The coefficient of friction is μ . If θ is the angle of inclination of the plane than tanθ is equal to
(a) μ
(b) 3μ
(c) 2μ
(d) 0.5μ
Ans:(b)
m(gsinθ + μgcosθ) = 2m(gsinθ – μ gcosθ)
3μcosθ = sinθ
tanθ =3 μ