A block of mass M slides down on a rough inclined plane with constant velocity. The angle made by the incline plane with horizontal is θ. The magnitude of the contact force will be :
(A)Mg✓ Correct
(B)Mgcosθ
(C)Mgsinθ+Mgcosθ
(D)Mgsinθ1+μ
Answer: (A)
Solution
Since the block moves with constant velocity, it is in equilibrium. The normal force N=Mgcosθ and friction force f=Mgsinθ. The contact force (resultant of N and f) has magnitude R=N2+f2=(Mgcosθ)2+(Mgsinθ)2=Mgcos2θ+sin2θ=Mg.
JEE Main · 2022 · 27 Jul 2022 · Shift 2 · Single correct option