Electric Motor

Q. The Fleming’s left hand rule can be applied to find the direction of magnetic field.

1. True
2. False

Q.

The direction of rotation of a DC motor, as shown below, is in the clockwise direction.
What is direction of the magnetic field?

1. Right to left

2. Vertically upwards

3. Vertically downwards

4. Left to right

Q. Rohan tests a new electric motor designed for appliances and realizes that motor is running incredibly slow. Which of the following can increase the rotation speed of the motor.
(i) By increasing the supply voltage
(ii) By using a stronger magnetic field
(iii) By increasing number of turns in armature

1. (i), (ii) & (iii)
   
2. Only (i)
   
3. Both (i) and (iii)
   
4. Both (ii) and (iii)
   

Q. In the given diagram of a DC motor, the direction of flow of electrons in the left arm is:

1. From A to B
2. From B to C
3. From B to A
4. From D to C

Q.

An electric motor converts mechanical energy into electrical energy.

1. True

2. False

Q. The speed of a DC motor can be altered with change in:

1. Area and number of turns in the coil
2. Magnetic field
3. Current
4. Polarity of the magnets

Q.

Electric motor converts:

1. Mechanical energy into electrical energy

2. Mechanical energy into heat energy

3. Electrical energy into heat energy

4. Electrical energy into mechanical energy

Q.

In an electric motor, the energy transformation is from

1. Electrical to chemical

2. Chemical to light

3. Mechanical to electrical

4. Electrical to mechanical

Q.

What is the principle of an electric motor?

Q. State true or false.
An electric motor converts mechanical energy into electrical energy.

1. True
2. False