3
\includegraphics[max width=\textwidth, alt={}, center]{edf90396-5e17-44ef-bf25-e09cbc5785ba-2_241_511_1676_817}
A small ring of mass 0.8 kg is threaded on a rough rod which is fixed horizontally. The ring is in equilibrium, acted on by a force of magnitude 7 N pulling upwards at \(45 ^ { \circ }\) to the horizontal (see diagram).
- Show that the normal component of the contact force acting on the ring has magnitude 3.05 N , correct to 3 significant figures.
- The ring is in limiting equilibrium. Find the coefficient of friction between the ring and the rod.