Kinetic Energy

Q.

An object of mass $15kg$ 15 kg is moving with a uniform velocity of $4m{s}^{-1}$. What is the kinetic energy possessed by the object?

Q.

A car is moving with a speed of $100km{h}^{-1}$. If the mass of the car is $950kg$, then its kinetic energy is

1. $0.367MJ$

2. $3.67J$

3. $3.67MJ$

4. $367J$

Q.

The K.E. of a body is increased most, by doubling its

1. mass

2. weight

3. speed

4. density

Q.

Greater the mass of a body, smaller is its kinetic energy.

1. True
2. False

Q.

Define kinetic energy.

Q. The ratio of kinetic energy of a planet at perigee and apogee during it motion around sun in elliptical orbit of eccentricity e is?

Q.

The kinetic energy of ${}^{\prime }{N}^{\prime }$ molecules of $H_2$ is $3J$ at $-{73}^{\circ }C$. The kinetic energy of the same sample of $H_2$ at $-{127}^{\circ }C$ is ___.

1. $12J$

2. $2.19J$

3. $9J$

4. $3J$

Q. A rocket is moving up with a velocity $v$. If the velocity of this rocket is suddenly tripled, what will be the ratio of two kinetic energies ?

1. $1$
2. $1:9$
3. $1:3$
4. $3$

Q.

The velocity of a body becomes half and mass becomes double. Its kinetic energy will be:

1. Two times

2. Half

3. Four times

4. None of these

Q.

The expression for kinetic energy is

1. $\left(\frac{1}{3}\right){\mathrm{mv}}^2$

2. $\left(\frac{1}{2}\right){\mathrm{mv}}^2$

3. $\left(\frac{1}{2\mathrm{m}}\right){\mathrm{v}}^2$

4. $\left(\frac{1}{2}\right)\mathrm{mv}$

Q. The kinetic energy of a substance is the energy with which the particles of the substance move. Kinetic energy changes with change in temperature. What substance would have the least amount of kinetic energy?

1. Water vapour at ${100}^{\circ }C$
2. Ice at $-2^{\circ }C$
3. Cool water at $2^{\circ }C$
4. Hot water at ${80}^{\circ }C$

Q. The kinetic energy possessed by a body with mass $m$ and moving with a velocity $v$ at a height $h$ is given by

1. $mgh$
2. $m{v}^2$
3. $\frac{1}{2}mgh$
4. $\frac{1}{2}m{v}^2$

Q. Find the kinetic energy of a body of mass $1kg$ moving with a uniform velocity of $10m{s}^{-1}$.

1. $0J$
2. $500J$
3. $50J$
4. $100J$

Q.

State two factors on which the kinetic energy of a body depends.

Q.

Calculate the change in kinetic energy of a moving body if its velocity is reduced to $\frac{1}{3}$of the initial velocity.