Kinetic Energy

A body of mass $5 \mathrm{kg}$ is moving with a momentum of $10 \mathrm{kg} \mathrm{m} {\mathrm{s}}^{-1}$. Now a force of $2 \mathrm{N}$ acts on the body in the direction of its motion for $5 \mathrm{s}$. The increase in the Kinetic energy of the body is _____ $\mathrm{J}$.

A car accelerates from rest of $u \mathrm{m} {\mathrm{s}}^{-1}$. The energy spent in this process is $E \mathrm{J}$. The energy required to accelerate the car from $u \mathrm{m} {\mathrm{s}}^{-1}$ to $2u \mathrm{m} {\mathrm{s}}^{-1}$ is $nE \mathrm{J}$. The value of $n$ is _____.

Two bodies are having kinetic energies in the ratio $16:9.$ If they have same linear momentum, the ratio of their masses respectively is:

The momentum of a body is increased by $50\%$. The percentage increase in the kinetic energy of the body is_$\_\_\_\_\_\_\_\%.$

A body is dropped on ground from a height $h_1$ and after hitting the ground, it rebounds to a height $h_2$. If the ratio of velocities of the body just before and after hitting ground is $4$, then percentage loss in kinetic energy of the body is $\frac{x}{4}$. The value of $x$ is _____.

Two bodies having same linear momentum have ratio of kinetic energy as $16:9$. Find the ratio of masses of these bodies.

A cable in the form of a spiral roll as shown in the figure has a linear density $0.25 \mathrm{kg} {\mathrm{m}}^{-1}$. It is uncoiled at a uniform speed of $2 \mathrm{m} {\mathrm{s}}^{-1}$. If the total length of the cable is $15 \mathrm{m}$, the work done in uncoiling is (neglect friction) 

If you could accelerate a proton $(\mathrm{m}=1.67\times {10}^{-27} \mathrm{kg})$ to a speed of $0.95 \mathrm{c}$. What would be its kinetic energy?

If a man speeds up by $1 \mathrm{m}/\mathrm{s}$, his kinetic energy increases by $44\%$. His original speed in $\mathrm{m}/\mathrm{s}$ is 

A bullet of mass $55 \mathrm{g}$ is moving with a velocity of $2400 \mathrm{km}/\mathrm{h}$, it penetrates $10 \mathrm{cm}$ into a wall before coming to rest. Calculate the K.E of the bullet (i) before it hit the wall. (ii) after it stops. (iii) Calculate the force exerted on the bullet by the wall.

If the momentum of a body is doubled, the kinetic energy becomes

If the K.E. of a body is increased by $300\%$, its momentum will increase by

Find percentage change in kinetic energy of given mass if velocity is changed by $20$ percent.

Calculate the kinetic energy of a bus of mass ${10}^4\mathrm{kg}$ moving with a speed of $108\mathrm{km} {\mathrm{h}}^{-1}$.

A uniform thin rod of length $L$, mass $m$ is lying on a smooth horizontal table. A horizontal impulse $P$ is suddenly applied perpendicular to the rod at one end. The total energy of the rod after the impulse is

"For one person, the kinetic energy of a body is zero whereas for another person it is not zero." Is it possible? Explain.

Can kinetic energy be negative? Explain.

Define kinetic energy and potential energy. Derive an expression for kinetic energy and potential energy.