Question

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.

• A. Statement 1 and statement 2
• B. Statement 1 and statement 3
• C. Statement 2 and statement 4
• D. statement 2 and statement 3

Answer 1

Answer: (B), (C)

Statement 2 and statement 4

The explanation for correct.

Statement 1.

1. The energy possessed by a body by its position or change in shape is called potential energy.
2. Potential energy increases by increasing the height.
3. The higher the object is from the ground level, the greater the potential energy is.
4. The energy possessed by a body by its motion is called kinetic energy.
5. Here the object is not moving, so the kinetic energy is zero.

Hence, the Statement is correct.

Statement 3

1. The energy possessed by a body by its motion is called kinetic energy.
2. Kinetic energy is directly proportional to the square of the speed of the body.
3. We know that Potential energy increases by increasing the height.
4. As long as the object has the height the object has the potential energy.
5. Here we have height as long as speed.

Hence, the statement is correct

Statement 4

1. The energy possessed by a body by its motion is called kinetic energy.
2. Kinetic energy is directly proportional to the square of the speed of the body.
3. We know that Potential energy increases by increasing the height.
4. As long as the object has the height the object has the potential energy.
5. Here we have the kinetic energy due to speed but we do not have potential energy because the height is zero.

Hence, the statement is correct

The explanation of incorrect.

Statement 2

1. The energy possessed by a body by its motion is called kinetic energy.
2. Kinetic energy is directly proportional to the square of the speed of the body.
3. We know that Potential energy increases by increasing the height.
4. As long as the object has the height the object has the potential energy.
5. Here we have height as long as speed.

Hence, the statement is incorrect.

So, the correct option is (B).