## 1. When a body falls freely towards the earth, then its total energy –

1. Zero
2. Infinite
3. Remains constant
4. None of the above

Memory: According to law of conservation of energy, energy can neither be created nor can be destroyed, it always remains constant.

## 2. SI unit of energy is ?

1. Erg
2. Joule
3. Newton
4. Watt

Memory: SI unit of work is also joule.

## 3. Capacity of doing work by a body is called ?

1. Work
2. Power
3. Energy
4. Force

Memory: No work can be done without energy. Ex. We can work due to energy stored in our body by eating food.

## 4. Energy is ?

1. Vector quantity
2. Scalar quantity
3. Both (A) and (B)
4. None of the above

Memory: Energy is scalar quantity as it has magnitude but no direction.

## 5. Energy developed in a body by virtue of work done on it is called ?

1. Electrical energy
2. Mechanical energy
3. Potential energy
4. Nuclear energy

Memory: No memory is available.

## 6. The capacity of doing work developed in a body due to its posistion is called ?

1. Static energgy
2. Dynamic energy
3. Potential energy
4. Gravitational energy

Memory: Potential energy is produced due to change in position of an object.

## 7. Potential energy of a body in the gravitational field of earth is ?

1. mgh
2. mgh2
3. mh/g
4. mgh/d2

Memory: Potential energy in earth’s gravitational field is defined by mgh.

Where,

• m = mass of the body
• g = acceleration due to gravity
• h = height of the object from surface of the earth

## 8. Energy possessed by a body due to its motion is known as ?

1. Potential energy
2. Kinetic energy
3. Gravitational energy
4. None of the above

Memory: Kinetic energy is only generated when the body is in motion. viz. Massive kinetic energy is produced when a meteor falls towards the earth’s surface.

## 9. When momentum is made double, then kinetic energy becomes ?

1. Two times
2. Three times
3. Four times
4. Five times

Memory: No memory is available.

## 10. Energy created by stretching or compressing spring is due to ?

1. Kinetic energy
2. Potential energy
3. Mechanical energy
4. Electrical energy