Kinetic Energy

Applying the work-energy theorem, derive an expression for the kinetic energy of the body.

Choose the correct relation between momentum and kinetic energy from the following options.

State the relation between momentum and kinetic energy.

Choose the correct formula for the rotational kinetic energy from the following options.

State the formula for the rotational kinetic energy.

A bullet has a mass of$100 \mathrm{g}$ and it moves with a velocity of $500 \mathrm{m} {\mathrm{s}}^{-1}$. It penetrates $25 \mathrm{cm}$ into a target which is not moving and then comes to rest. Find the kinetic energy possessed by the bullet and also the average retarding force offered by the target.

If a bullet of mass $70 \mathrm{g}$ moves with a velocity of $750 \mathrm{m} {\mathrm{s}}^{-1}$. It penetrates $30 \mathrm{cm}$ into a target which is not moving and then comes to rest. Find the kinetic energy possessed by the bullet and also the average retarding force offered by the target. 

An electron and a proton are moving under the influence of mutual forces. In calculating the change in the kinetic energy of the system during motion, one ignores the magnetic force of one on another. This is because

The average kinetic energy of a molecule is,

In a ballistics demonstration a police officer fires a bullet of mass $50 \mathrm{g}$ with speed $200\mathrm{ }{\mathrm{ms}}^{-1}$ on soft plywood of thickness $2\mathrm{ }\mathrm{cm}$. The bullet emerges with only $10\%$ of its initial kinetic energy. The emergent speed of the bullet is

Which of the following statements is incorrect?

The kinetic energy of an object _______with its speed.

_______ energy is the energy possessed by an object due to its motion.

Calculate the work required to be done to stop a car of $1500 \mathrm{kg}$ moving at a velocity of $60 {\mathrm{kmh}}^{-1}$?

An object of mass, m is moving with a constant velocity, v. How much work should be done on the object in order to bring the object to rest?

A  $40 \mathrm{N}$ object is released from a height of $10 \mathrm{m}$. Just before it hits the ground, its kinetic energy, in joules is _______

Two objects of masses $1\times {10}^{-3}\mathrm{k}\mathrm{g}$ and $4\times {10}^{-3}\mathrm{ }\mathrm{k}\mathrm{g}$ have equal momentum. What is the ratio of their kinetic energies?

A light and heavy body have equal momenta which one has greater KE?

An example of K.E. would be

Two bodies of masses m₁ and m₂ have equal KE. If P₁ and P₂ are their respective momentum, then ratio. P₁ : P₂ is