Three blocks with masses $m, 2m $ and $3 m$ are connected by strings, as shown in the figure. After an upward force $F$ is applied on block $m,$ the masses move upward at constant speed $v.$ What is the net force on the block of mass $2\ m\ ?\, (g$ is the acceleration due to gravity$)$
A block of mass $M$ is pulled along a horizontal frictionless surface by a rope of mass $m$. If a force $P$ is applied at the free end of the rope, the force exerted by the rope on the block will be
A block $B$ is placed on block $A$. The mass of block $B$ is less than the mass of block $A$. Friction exists between the blocks, whereas the ground on which the block $A$ is placed is taken to be smooth. $A$ horizontal force $F$, increasing linearly with time begins to act on $B$. The acceleration ${a_A}$ and ${a_B}$ of blocks $A$ and $B$ respectively are plotted against $t$. The correctly plotted graph is
In which of the following cases is the contact force between $A$ and $B$ maximum $(m_A = m_B = 1 kg)$
Two blocks are connected by a string as shown in the diagram. The upper block is hung by another string. A force $F$ applied on the upper string produces an acceleration of $2\,m/{s^2}$ in the upward direction in both the blocks. If $T$ and $T'$ be the tensions in the two parts of the string, then $T$ and $T'$