Two smooth rings $A$ and $B$ are connected by a string. Another string connects Ring  $A$ and block, if strings are tight then at the given moment :

Two blocks of mass $2 \mathrm{kg}$ and $3 \mathrm{kg}$ are placed in a cart. A variable force $F$ is acting on the cart. At an instant acceleration of different blocks and cart are as shown. Find value of $F$ at this instant (mass of cart is $10 \mathrm{kg}$ ) All accelerations are horizontal.

A mass of $1 \mathrm{kg}$ is suspended by a string $A$. Another string $C$ is connected to its lower end (see figure). If a sudden jerk is given to $C$, then