A transformer of 100% efficiency has 200 turns in the primary coil and 40000 turns in secondary coil. It is connected to a 220 V main supply and secondary feeds to a 100 kΩ resistance. The potential difference per turn is
 
1.  1.1 V
 
2.  25 V
 
3.  18 V
 
4.  11 V
Subtopic:  Transformer |
 59%
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A thin convex lens of refractive index 1.5 has 20 cm focal length in air. If the lens is completely immersed in a liquid of refractive index 1.6, its focal length will be
 
1.  -160 cm
 
2.  - 100 cm
 
3.  + 10 cm
 
4.  +100 cm
Subtopic:  Lens Makers' Formula |
 55%
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SI unit of permittivity is
 

1.  C2m2N2

2.  C2m-2N-1

3.  C2m2N-1

4.  C-1m2N-2

Subtopic:  Coulomb's Law |
 69%
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A spherical drop of capacitance 1μF is broken into eight drops of equal radius. Then, the capacitance of each small drop is
1.   μF
2.   μF
3.   μF
4.  8 μF
Subtopic:  Capacitance |
 52%
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A simple harmonic oscillator consists of a particle of mass m, and an ideal spring with spring constantk. The particle oscillates with a time period T. The spring is cut into two equal parts, Of one part oscillates with the same particles, the time period will
 
1.  2T