Three blocks of masses $m_1=4 \,kg , m_2=2 \,kg , m_3=4 \,kg$ are connected with ideal strings passing over a smooth. massless pulley as shown in figure. The acceleration of blocks will be ......... $m / s ^2$ $\left(g=10 \,m / s ^2\right)$

In the given figure acceleration of wedge $'A'$ is $10\ m/s^2$ along the inclined plane. (There is no friction between $A$ $\&$ $B$ and $A$ $\&$ fixed inclined plane.) Then acceleration of block $'B'$ will ............ $m/s^2$

Find velocity of block ' $B$ ' at the instant shown in figure $........\,m/s$

A balloon of mass $m$ is descending down with an acceleration $\frac{g}{2}$.  How much mass should be removed from it so that it starts moving up with same acceleration?

If pulleys shown in the diagram are smooth and massless and $a_1$ and $a_2$ are acceleration of blocks of mass $4 \,kg$ and $8 \,kg$ respectively, then

In the figure shown the velocity of lift is $2\,m / s$ while string is winding on the motor shaft with velocity $2\,m / s$ and block $A$ is moving downwards with a velocity of $2\,m / s$, then find out the velocity of block $B -$