A particle moves along the x-axis under the influence of a force $F(x) = -kx^2$. If the particle moves from $x = a$ to $x = 2a$, the work done by the force is:

A force of 1200 N acting on a stone by means of rope slides the stone through a distance of 10 m in a direction inclined at ${60^0}$ to the force. The work done by the force is [Joules].

Force of 4 N is applied on a body of mass 20 kg. The work done in 3rd second is

A force $\vec{F} = (3\hat{i} + 4\hat{j})$ N acts on a particle and displaces it by $\vec{s} = (5\hat{i} - 2\hat{j})$ m. The work done by the force is:

A block of mass $m$ is placed on a smooth horizontal surface. A constant force $F$ is applied at an angle $heta$ above the horizontal. If the block covers a distance $d$, the work done by the force $F$ is:

Two observers are situated in different inertial reference frames. Then

A point of application of a force ${\rm{\vec F}} = 5\hat i - 4\hat j + 2\hat k$ is moved from $\overrightarrow {{{\rm{r}}_1}} = 2\hat i + 7\hat j + 4\hat k\,to\,\overrightarrow {{{\rm{r}}_2}} = 5\hat i + 2\hat j + 3\hat k$ the work done is

A force of 20 N acts on a box, moving it 4 meters horizontally. If the force is applied at an angle of 30° to the horizontal, what is the work done?

You lift a heavy book from the floor of the room and keep it in the book–shelf having a height 2 m. In this process you take 5 seconds. The work done by you will depend upon

A particle moves from a point $( - 2\hat i + 5\hat j)$ to $(4\hat j + 3\hat k)$ when a force of $(4\hat i + 3\hat j)N$ is applied. How much work has been done by the force?

A body constrained to move in the y-direction is subjected to force ${\bf{F}} = 2\hat i + 15\hat j + 6\hat k$N. The work done by this force in moving the body through a distance of 10 m along y-axis is