A student wishes to analyse the conditions under which a block of mass can remain at…
PHYSICS · Multi-part · AP · Physics 1: Algebra-based · Force and Translational Dynamics · Force and Translational Dynamics
Problem
A student wishes to analyse the conditions under which a block of mass m can remain at rest on a smooth fixed plane that is inclined at an angle θ to the horizontal.
(i) Draw a clearly labelled free-body diagram of the block, choosing axes parallel and perpendicular to the plane.
(ii) Using the diagram, write the equations expressing that the net force along the plane and the net force perpendicular to the plane are each zero.
(iii) Explain, with reference to these equations, why no force component acts to move the block perpendicular to the plane and identify the physical quantity that balances the component of weight in that direction.
(iv) Show that, for equilibrium, any external force F applied parallel to the plane and directed up the incline must satisfy F=mgsinθ. State clearly the assumptions made.