If a force of constant magnitude acts in a direction perpendicular to the motion of a particle,then its

$A$ uniform chain of length $L = 2\,m$ is kept on a table such that a length $\ell = 60\,cm$ hangs freely from the edge of the table. The total mass of the chain is $M = 4\,kg$. The work done in pulling the entire chain onto the table is ............. $J$. (Take $g = 10\,m/s^2$)

$A$ particle moves from position $3\hat i + 2\hat j - 6\hat k$ to $14\hat i + 13\hat j + 9\hat k$ due to a uniform force of $(4\hat i + \hat j + 3\hat k) \, N$. If the displacement is in meters,the work done will be ......... $J$.

How much work does a pulling force of $40 \,N$ do on a $20 \,kg$ box in pulling it $8 \,m$ across the floor at a constant speed? The pulling force is directed at $60^\circ$ above the horizontal.

When an object is dragged $10 \, m$ along a road,a frictional force of $200 \, N$ acts in the direction opposite to its motion. What is the work done by the frictional force on the object (in $, J$)?

$A$ block of mass $m$ is kept in an elevator which starts moving downward with an acceleration $a$ as shown in the figure. The block is observed by two observers $A$ and $B$ for a time interval $t_0$. The observer $B$ (who is on the ground) finds that the work done by gravity on the block is: