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\includegraphics[max width=\textwidth, alt={}, center]{9bb53600-e7ba-4228-84ae-d8ddf7649387-2_478_597_1398_776}
Particles \(A\) and \(B\), of masses 0.2 kg and 0.3 kg respectively, are connected by a light inextensible string. The string passes over a smooth pulley at the edge of a rough horizontal table. Particle \(A\) hangs freely and particle \(B\) is in contact with the table (see diagram).
- The system is in limiting equilibrium with the string taut and \(A\) about to move downwards. Find the coefficient of friction between \(B\) and the table.
A force now acts on particle \(B\). This force has a vertical component of 1.8 N upwards and a horizontal component of \(X\) N directed away from the pulley.
- The system is now in limiting equilibrium with the string taut and \(A\) about to move upwards. Find \(X\).