Electric Generator

Q.

A conducting circular loop of radius $r$ carries a constant current $i$. It is placed in a uniform magnetic field, such that is perpendicular to the plane of the loop. The magnetic force acting on the loop is.

Q.

Explain the underlying principle and working of an electric generator by drawing a labelled diagram. What is the function of brushes? [5 MARKS]

Q.

A dynamo converts ____________________.

Q.

Slip rings are used in AC generator.

1. True
2. False

Q. The arm of an electric generator with split rings is rotated in clockwise direction. The deflection of the galvanometer will _______.

1. be towards left
2. be towards right
3. oscillates between left and right.
4. Can not be determined

Q. Which of the following statements are true?

1. AC generator supplies direct current.
2. DC generator has a commutator.
3. DC generator supplies alternating current.
4. AC generator has slip rings.

Q. How does a generator work?

Q. In an electric generator, the two ends of the coil are connected to the two _________.

1. slit rings
2. carbon brushes
3. poles of the magnet
4. ends of a battery

Q. what will happen if a split ring is used in place of slip ring in an AC generator?

Q.

The arm of an electric generator with split rings is rotated clockwise the deflection of the galvanometer will be:

1. left, continuously.

2. right, continuously.

3. shifts between left and right.

4. there will be no deflection.

Q. This section contains 1 Assertion-Reason type question, which has 4 choices (a), (b), (c) and (d) out of which ONLY ONE is correct.
इस खण्ड में 1 कथन-कारण प्रकार का प्रश्न है, जिसमें 4 विकल्प (a), (b), (c) तथा (d) दिये गये हैं, जिनमें से केवल एक सही है।

A : Voltmeter is much better than potentiometer for measuring emf of cell.
A : सेल के वि.वा.ब. के मापन के लिए विभवमापी की अपेक्षा वोल्टमीटर बेहतर होता है।

R : A potentiometer draws no current while measuring the emf of the cell.
R : सेल के वि.वा.ब. का मापन करते समय विभवमापी से कोई धारा प्रवाहित नहीं होती है।

1. Both (A) and (R) are true and (R) is the correct explanation of (A)
   
   (A) तथा (R) दोनों सही हैं तथा (R), (A) का सही स्पष्टीकरण है
2. Both (A) and (R) are true but (R) is not the correct explanation of (A)
   
   (A) तथा (R) दोनों सही हैं लेकिन (R), (A) का सही स्पष्टीकरण नहीं है
3. (A) is true but (R) is false
   
   (A) सही है लेकिन (R) गलत है
4. (A) is false but (R) is true
   
   (A) गलत है लेकिन (R) सही है

Q.

What happens in alternating current?

Q.

In the figure given below, a coil is placed between two permanent magnets and it is rotated with the help of an axle on which two rings R1 and R2 are internally attached. B1 and B2 represent metallic brushes. G represents galvanometer.

As the coil starts to rotate, the current flows through ABCD as shown. The coil is rotating in:

1. Clockwise direction

2. Anti-clockwise direction

3. Either Clockwise or anti-clockwise

4. Can't be said

Q.

In an electric generator, the voltage induced across the terminals of the copper coil when it rotates in the magnetic field is

1. An alternating voltage

2. Direct voltage

3. Step-up voltage

4. Step down voltage