Question

In the shown system $m_1>m_2$. Thread $QR$ is holding the system. If this thread is cut, then just after cutting :

• A. acceleration of mass $m_1$ is zero and that of $m_2$ is directed upward
• B. acceleration of mass $m_2$ is zero and that of $m_2$ is directed upward
• C. acceleration of both the blocks will be same
• D. acceleration of system is given by $\left(\frac{m_1-m_2}{m_1+m_2}\right)kg$, where $k$ is a spring factor

Answer 1

The correct option is A acceleration of mass $m_1$ is zero and that of $m_2$ is directed upward

On cutting the string the resultant force of $m_1$ remains zero because its weight is balanced by the tension in the spring. but on block $m_2$ a resultant upward force $(m_1-m_2)g$ is developed. This block $m_1$ will have no resultant acceleration whereas $m_2$ does have an upward acceleration of $\frac{(m_1-m_2)g}{m_2}$.