Power Generator

Q.

What is the reason behind the use of electromagnets instead of permanent magnets in power generators.

1. The permanent magnets become shiny with time.

2. The strength of permanent magnet increases with time.

3. The shape of permanent magnets is huge.

4. The strength of permanent magnet decreases with time.

Q.

The amplitude of alternating EMF depends on

Q.

The direction of rotation of a motor remains unchanged if ___.

1. the direction of current is reversed

2. the direction of the magnetic field is reversed

3. both current and magnetic field direction is reversed simultaneously.

4. the direction of current is changed without changing the direction of magnetic field

Q. How induced current changes after half rotation in an AC generator?

Q. Explain the working of AC and DC generator.

Q. Why are the poles of the magnet used in Generator is made concave?

Q. What is the name of the system that is used for house wiring?

1. square system
2. circle system
3. ring system
4. rectangle system

Q. Match the following devices to their corresponding energy conversions.

1. Mechanical to electrical
2. Electrical to mechanical
3. Electrical to light

Q. Explain the working of electric generator.

Q. Which of the following is not an essential component of a domestic electrical circuit?

1. Earth wire
2. MCB
3. Socket
4. Electric iron

Q. Question 6
State whether the following statements are true or false.
(a) An electric motor converts mechanical energy into electrical energy.
(b) An electric generator works on the principle of electromagnetic induction.
(c) The field at the centre of a long circular coil carrying current will be parallel straight lines.
(d) A wire with a green insulation is usually the live wire of an electric supply.

Q.

Describe the working of an AC generator with the help of a labeled circuit diagram. What changes must be made in the arrangement to convert it to a DC generator?

Q. What is Electrical generator?

Q.

What is the speciality of a power generator?

1. Power generator converts only chemical energy into electrical energy.

2. Power generator converts any type of energy into electrical energy.

3. Power generator converts electrical energy into chemical energy.

4. Power generator converts electrical energy into mechanical energy.

Q. If the ends of a wire loop are attached to two half-circular metal strips, arranged so that the two strips almost form a complete circle, and those strips are contacted by two "brushes" which connect to opposite poles of a battery, what polarity of voltage will be measured as the loop is rotated counter-clockwise?

​​​​​​​

1. Right Postive, Left Negative

2. Right Negative, Left Positive
3. There is actually no current.
4. Can’t be determined

Q.

Choose the correct answer.

Which of these converts electrical energy to mechanical energy?

1. Light bulb

2. Electric iron

3. Electric motor

4. Battery

Q.

what is the function of carbon brushes in ac generator ?

Q. Is split and slip rings types of commutators?

Q.

How a split ring works in a motor

Q.

Which one of the following is a type of power generator?

1. Dynamo

2. Ammeter

3. DC motor

4. Voltmeter

Q. Out of an A.C. generator and a D.C. generator:

(a) which one uses a commutator (split rings)?
(b) which one uses slip rings?

Q. Explain the underlying principle and working of an electric generator by drawing a labelled diagram. What is the function of brushes?

Q.

What is the frequency of alternating current (AC) generated for distribution in India?

1. 100 Hz

2. 500 Hz

3. 1000 Hz

4. 50 Hz

Q.

Power generators are used in the centres where large quantities of electricity is generated and is distributed.

1. True

2. False

Q. In what respect does the construction of an AC generator differ from that of a DC generator?

Q. Live wire carries current at high voltage.

1. True
2. False

Q. State what would happen to the direction of rotation of a motor if:
Both current and magnetic field were reversed simultaneously.

Q. What change should be made in an a.c. generator so that it may become a d.c. generator?

Q. Explain the construction and working of electric motors in short.

Q. State what would happen to the direction of rotation of a motor if:
the current were reverse