6.
\begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{2def617f-3c25-4458-8500-8e20ba7c1e53-4_451_734_964_607}
\captionsetup{labelformat=empty}
\caption{Fig. 2}
\end{figure}
Figure 2 shows a particle \(A\) of mass 5 kg , lying on a smooth horizontal table which is 0.9 m above the floor. A light inextensible string of length 0.7 m connects \(A\) to a particle \(B\) of mass 2 kg . The string passes over a smooth pulley which is fixed to the edge of the table and \(B\) hangs vertically 0.4 m below the pulley.
When the system is released from rest,
- show that the magnitude of the force exerted on the pulley is \(\frac { 10 \sqrt { 2 } } { 7 } \mathrm {~g} \mathrm {~N}\),
- find the speed with which \(A\) hits the pulley.
When \(A\) hits the pulley, the string breaks and \(B\) subsequently falls freely under gravity.
- Find the speed with which \(B\) hits the ground.