(i)[3]
Find the string tension.
(ii)[4]
Find the contact force components, frictional and normal, acting on $B$.
(iii)[2]
Since the equilibrium is limiting, find the coefficient of friction between the bead and the rod.
Mathematics 9709 · AS & A Level · Forces and equilibrium
Forces and equilibrium — practice question
A small smooth ring $R$, with mass $0.6\,\text{kg}$, is placed on a light inextensible string of length $100\,\text{cm}$. One end of the string is fixed at point $A$. A small bead $B$ of mass $0.4\,\text{kg}$ is attached to the other end of the string, and it is threaded on a fixed rough horizontal rod that passes through $A$. The system is in equilibrium, with $B$ located $80\,\text{cm}$ from $A$.
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