Potential Energy of an Object at a Height

Q.

What Do You Mean By Kinetic Energy?

Q. in a new unit system, unit of time is equal to 20 second, 1 unit of mass is 10kg and 1 unit of lenght is 5 m . in the new system of units, 1 unit of energy is equal to ?

Q.

Is kinetic energy constant in circular motion?

Q.

When a ball is thrown upward, its total energy:

1. increases

2. decreases

3. remains same

4. none of these

Q. A body's potential energy depends on its:

1. mass
2. position
3. acceleration
4. velocity

Q.

Potential energy is the energy possessed by an object due to its.

Q.

What do you mean by conservation of mechanical energy? State the condition when it holds

Q.

Find the energy possessed by an object of mass $10kg$ when it is at a height of $6m$above the ground. (Given $g=9.8m{s}^{-2}$).

Q. A girl of weight 500 N runs up the stairs of a plane in 10 s. The stairs are 5 m high. What is the average power utilised to climb to the top?

1. 250 W
2. 100 W
3. 1000 W
4. 50 W

Q.

An arrow fired from a bow has which kind of energy change?

1. 20J

2. 25J

3. 30J

4. 35J

Q.

An $800g$ ball is pulled up a slope as shown in the diagram. Calculate the potential energy it gains.

1. $1.96J$

2. $1.568J$

3. $7.84J$

4. $1.225J$

Q. The P.E.of a body at a certain height is 200J when it is released. The K.E when it just touches the surface is:

1. Equal to potential energy
2. Greater than potential energy
3. Lesser than potential energy
4. None of the above

Q.

What kind of energy is possessed by a running athlete?

Q.

A body of mass $20kg$ is dragged through a distance of $8m$ in $10s$ by a force of $20N$. find the work done by the force and the power consumed.

Q.

The object of mass of 1 kg has a potential energy of 1 joule relative to the ground, when it is at a height of:

1. 0.102 m

2. 1 m

3. 9.8 m

4. 32 m

Q. Where is the roller coaster gaining potential energy?

1. A to B
2. C to D
3. B to C
4. The roller coaster is always losing potential energy

Q.

The energy possessed by a magnet is called ___.

1. 1: 1

2. 2: 3

3. 5: 7

4. 3: 2

Q.

Define: potential energy and give the mathematical expression of potential energy.

Q.

Read the statements carefully

Statement 1: A book kept on the book shelf has potential energy.

Statement 2. A book falling down but has not reached the ground yet has kinetic energy only.

Statement 3. A book falling down but has not reached the ground yet has kinetic energy and potential energy.

Statement 4. A falling book on landing has kinetic energy only.

Which of the following statement are correct? State the reason for your answer.

1. Statement 1 and statement 2

2. Statement 1 and statement 3

3. Statement 2 and statement 4

4. statement 2 and statement 3

Q.

Shishir was playing with a spring. He was compressing and releasing it. Suddenly he noticed that a ball, when kept on a spring, attains a certain height after it is compressed and released. What is the change of energy?

1. 3m

2. 5m

3. 7m

4. 9m

Q.

What happens to the potential energy of a body if its mass is increased by three times.

Q. A ball strikes with angle 45 degree to the horizontal. The coefficient of restitution is1/2.then fractional loss in kinetic energy is?

Q.

A ball is falling from a height h, After it has fallen to height h/2, it will possess -

1. Neither potential nor kinetic energy

2. Only kinetic energy

3. Both potential and kinetic energy

4. Only potential energy

Q.

Differentiate between kinetic energy and potential energy

Q.

A freely falling stone has

1. only potential energy

2. only kinetic energy

3. both, kinetic energy and potential energy

4. None of these.

Q.

Magnetic energy can be classified as:

1. Kinetic energy

2. Potential energy

3. Both (A) and (B)

4. None of the above

Q.

Can you say if the following objects have energy? If they do, identify whether the energy is kinetic, potential or combination of the two.

1. A ceiling fan which has been switched off.
2. A man climbing a hill.
3. A flying bird.
4. Water in the reservoir of a dam.
5. A spring expanded beyond its normal shape.
6. A rubber band lying on a table.
7. A stretched rubber band lying on the ground.

Q.

A hydrogen balloon has greater potential energy at higher altitudes. Is it true or false?

1. True
2. False

Q.

Answer the following:

Give some examples of kinetic energy.

Q. A ball collides directly with another ball at rest and is brought to rest by the impact. If half of the initial kinetic energy is lost in the impact, then the coefficient of restitution is 1/4 1/2 3/4 1/1.414