A block of mass is kept at rest on a smooth plane inclined at an angle to the horizontal.
PHYSICS · Multi-part · AP · Physics 1: Algebra-based · Force and Translational Dynamics · Force and Translational Dynamics
Problem
A block of mass m is kept at rest on a smooth plane inclined at an angle θ to the horizontal.
(i) Draw a clear free-body diagram of the block and label all the forces acting on it.
(ii) Using the diagram, explain why the normal reaction exerted by the plane on the block is less than the weight of the block. Derive the relation N=mgcosθ.
(iii) For θ=60∘, calculate the ratio mgN. Comment on the physical meaning of your result.