A uniform chain of length $2\,m$ is kept on a table such that a length of $60\,cm$ hangs freely from the edge of the table. The total mass of the chain is $4\,kg$. What is the work done in pulling the entire chain on the table ................ $\mathrm{J}$
$7.2$
$3.6$
$120$
$1200$
The force constant of a wire is $k$ and that of another wire is $2k.$ When both the wires are stretched through same distance, then the work done
A bullet of mass $25\,g$ moving with a velocity of $200\,m/s$ is stopped within $5\,cm$ of the target. The average resistance offered by the target is ............... $\mathrm{kN}$
A particle is moving in a circular path of radius a under the action of an attractive potential $U = - \frac{k}{{2{r^2}}}$ Its total energy is
In the figure, the ball $A$ is released from rest when the spring is at its natural (unstretched) length. For the block $B$ of mass $M$ to leave contact with the ground at some stage, the minimum mass of $A$ must be
A particle gets displaced by $\Delta \,\vec r = \,(2\hat i + 3\hat j + 4\hat k)$ $m$ under the action of a force $\vec F = \,(7\hat i + 4\hat j + 3\hat k)$ The change in its kinetic energy is ............... $\mathrm{J}$