Block–table interaction under action–reaction forces
PHYSICS · Multi-part · AP · Physics 1: Algebra-based · Force and Translational Dynamics · Force and Translational Dynamics
Problem
Block–table interaction under action–reaction forces
(i) State Newton’s third law of motion.
(ii) A wooden block of mass 2kg rests on a horizontal table. Draw separate free-body diagrams for (a) the block and (b) the portion of the table just beneath the block, clearly labelling all forces.
(iii) Identify the action–reaction force pairs acting between the block and the table and, using the equations of equilibrium for the block, show that their magnitudes are equal.
(iv) Give one reason why the equal and opposite forces named in part (iii) do not cancel each other for the block.