Assignment

Which of the following statement is incorrect about kinetic energy?

Work done by friction is

The force acting on a body moving along $x$-axis is $\mathrm{F}=\left(3{\mathrm{x}}^2\right)\mathrm{N}$. The work done required to move it from $x=0$ to $x=3 \mathrm{m}$ is

If a body of mass $2 \mathrm{kg}$ moving with constant velocity $2 \mathrm{m} {\mathrm{s}}^{-1}$, then the kinetic energy of the body is

If the momentum of the body is increased by $20\%$, then percentage increase in its kinetic energy of the body is

Which quantity remains conserved in all types of collisions?

If a mass $m$ collides elastically with another identical mass at rest in oblique manner, then after collision both the masses move at an angle of

In a conservative field, the potential energy $U$ as a function of position $x$ is given by $U=x^2$. Then the corresponding conservative force is given by