| 1 |
The rod of unit length is moving at 30 o through a magnetic field of 1 T. If the velocity of rod is 1 m/s, then induced emf in the rod will be given by |
- A. I V
- B. 0.25 V
- C. 0.5 V
- D. 0.6 V
|
| 2 |
The Lenz's law is also statement of: |
- A. Law of conservation of mass
- B. Law of conservation of charge
- C. Law of conservation of energy
- D. Law of conservation of momentum
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| 3 |
The induced emf in a coil is proportional to: |
- A. Magnetic flux through the coil
- B. Rate of change of Magnetic flux through the coil
- C. Area of the coil
- D. Product of magnetic flux flux and area of the coil
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| 4 |
Energy stored in an inductor is: |
- A. 1/2L<sup>2</sup>I
- B. 1/2L<sup>2</sup>/I
- C. <sub>1/2LI</sub><sup>2</sup>
- D. 1/2LI
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| 5 |
The unit of induced emf is |
- A. Ampere
- B. Volt
- C. Joule/coulomb
- D. Both (b) and (c)
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| 6 |
A simple device that prevents the direction of current from changing is called. |
- A. Commutator
- B. Rotor
- C. Armature
- D. Detector
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| 7 |
Efficiency of transformer does not affected by |
- A. Input voltage
- B. Core of transformer
- C. Insulation between sheet
- D. Resistance of coils
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| 8 |
The induction can be increased by winding the wire around a core made of. |
- A. Copper
- B. Silicon
- C. Iron
- D. Aluminum
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| 9 |
What is the co-efficient of mutual inductance, when the magnetic flux changes by 2 x 10<sup>-2</sup> Wb, and change in current is 0.01 A? |
- A. 2 H
- B. 3 H
- C. 1/2 H
- D. Zero
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| 10 |
A.C is converted into D.C by |
- A. Dynamo
- B. Rectifier
- C. Motor
- D. Transformer
|