In the figure,two blocks $M$ and $m$ are tied together with an inextensible and light string. The mass $M$ is placed on a rough horizontal surface with coefficient of friction $\mu$ and the mass $m$ is hanging vertically against a smooth vertical wall. The pulley is frictionless. Choose the correct statement$(s)$ related to the tension $T$ in the string.

Two blocks ($P$ and $Q$) with masses $2 \text{ kg}$ and $1.5 \text{ kg}$ respectively are joined by a massless thread. These blocks are mounted on a frictionless pulley which is fixed on the edge of a cube $(S)$, as shown in the figure. Block $P$ is positioned on the top surface which has no friction, and block $Q$ is in contact with the side surface, which has a coefficient of friction $\mu$. The cube $(S)$ moves towards the right with an acceleration of $g/2$, where $g$ is the gravitational acceleration. During this movement, the blocks $P$ and $Q$ remain stationary relative to the cube. The value of $\mu$ is . . . . . . . (Take $g = 10 \text{ m/s}^2$)

$A$ person of mass $60\, kg$ is inside a lift of mass $940\, kg$ and presses the button on the control panel. The lift starts moving upwards with an acceleration of $1.0\, m/s^2$. If $g = 10\, m/s^2$,the tension in the supporting cable is .......... $N$.

$A$ man is standing on a spring platform. The reading of the spring balance is $60\, kg$ wt. If the man jumps off the platform,what happens to the reading of the spring balance?

$A$ bouncing ball of mass $200 \,g$ falls from a height of $5 \,m$ onto a horizontal ground. After every impact with the ground, the velocity of the ball decreases by $\frac{1}{2}$ times. The total momentum the ball imparts to the ground after $3$ impacts is (Let $g=10 \,m/s^2$):

$A$ spring is compressed between two blocks of masses $m_1$ and $m_2$ placed on a horizontal surface as shown in the figure. When the blocks are released,they have initial velocities $v_1$ and $v_2$ as shown. The blocks travel distances $x_1$ and $x_2$ respectively before coming to rest due to friction. The ratio $\left( \frac{x_1}{x_2} \right)$ is