The kinetic energy $(KE)$ acquired by a mass $m$ in travelling a certain distance $d$,starting from rest,under the action of a constant force $F$ is ..........

When a force of $50 \, N$ is applied to an object,it undergoes a displacement of $10 \, m$ at an angle of $60^\circ$ with the direction of the force. The work done is ......... $J$.

$A$ particle gets displaced by $\Delta \vec{r} = (2\hat{i} + 3\hat{j} + 4\hat{k}) \text{ m}$ under the action of a force $\vec{F} = (7\hat{i} + 4\hat{j} + 3\hat{k}) \text{ N}$. The change in its kinetic energy is ............... $\text{J}$.

Two persons $A$ and $B$ perform the same amount of work in moving a body through a certain distance $d$ with the application of forces acting at angles $45^{\circ}$ and $60^{\circ}$ with the direction of displacement,respectively. The ratio of the force applied by person $A$ to the force applied by person $B$ is $\frac{1}{\sqrt{x}}$. The value of $x$ is ...... .

$A$ force $\vec F = 2\hat i - 3\hat j + 7\hat k \text{ (N)}$ acts on a particle which undergoes a displacement of $\vec S = 7\hat i + 3\hat j - 2\hat k \text{ (m)}$. Calculate the work done by the force in $J$.

$A$ particle of mass $100 \ g$ is projected vertically upwards with a speed of $5 \ m/s$. What is the work done by the force of gravity during the time the particle returns to the starting point? (in $J$)