| 1 |
The direction of induced current is always so as to oppose the change which causes the current is: |
- A. Faraday's law
- B. Lenz's law
- C. Ohm's law
- D. Kirchhoff's 1st rule
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| 2 |
A.C. Generator based upon the |
- A. Lenz's law
- B. Maxwell's relation
- C. Faradays law of electromagnet induction
- D. Mutual induction
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| 3 |
Energy density of an inductor is: |
- A. UM=1/2μ<sub>∘</sub>/B<sup>2</sup>
- B. Um = 2μ<sub>∘</sub>/B
- C. UM = 1/2B<sup>2</sup>/μ<sub>∘</sub>
- D. Um = 2B<sup>2</sup>/μ<sub>∘</sub>
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| 4 |
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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| 5 |
Induced emf in A.C. generator can be increased by |
- A. Decreasing area of coil
- B. Decreasing magnetic field
- C. Increasing area of coil
- D. Slowing down speed of coil
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| 6 |
<br> |
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| 7 |
Unit of self inductance is |
- A. Weber
- B. Tesla
- C. Henry
- D. Farad
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| 8 |
A metal rod of 1 m is moving at a speed of 1 ms-1 in a direction making an angle 30<sup> o</sup> with 0.5 T magnetic field . The emf produced is. |
- A. 0.25 N
- B. 2.5 N
- C. 0.25 V
- D. 2.5 V
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| 9 |
DC generator by william Sturgeon in: |
- A. 1894
- B. 1961
- C. 1834
- D. 1961
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| 10 |
If we make magnetic field stronger the value of induced current is. |
- A. Decreased
- B. Increased
- C. Vanishes
- D. Remain constant
|