OCR MEI Paper 1 Specimen — Question 14

Exam BoardOCR MEI
ModulePaper 1 (Paper 1)
SessionSpecimen
TopicNewton's laws and connected particles

14 Blocks A and B are connected by a light rigid horizontal bar and are sliding on a rough horizontal surface. A light horizontal string exerts a force of 40 N on B .
This situation is shown in Fig. 14, which also shows the direction of motion, the mass of each of the blocks and the resistances to their motion. \begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{ff44367e-c992-4e79-b255-5a04e0b8e21e-11_266_1283_664_255} \captionsetup{labelformat=empty} \caption{Fig. 14}
\end{figure}
  1. Calculate the tension in the bar. The string breaks while the blocks are sliding. The resistances to motion are unchanged.
  2. Determine
    • the magnitude of the new force in the bar,
    • whether the bar is in tension or in compression.