Explanation:
A potentiometer has very large resistance. To read load voltage or voltage across any circuit element, potentiometer is connected parallel across it. Thus, the load voltage or circuit voltage gets applied across the potentiometer but as the resistance is very high compared to load resistance, you can safely assume their is almost no current flowing through potentiometer. As power = VI, the power loss in potentiometer is almost equal to zero as current through it remains zero.
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What physical quantities may X and Y represent ? (Y represents the first mentioned quantity)
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(a) Pressure v/s temperature of a given gas (constant volume) |
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(b) Kinetic energy v/s velocity of a particle |
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(c) Capacitance v/s charge to give a constant potential |
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(d) Potential v/s capacitance to give a constant charge |
The frequency of light ray having the wavelength 3000 Å is
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(a) 9 × 1013 cycles/sec |
(b) 1015 cycles/sec |
(c) 90 cycles/sec |
(d) 3000 cycles/sec |
The electron mobility in N-type germanium is 3900 cm2/v-s and its conductivity is 6.24 mho/cm, then impurity concentration will be if the effect of cotters is negligible
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(a) 1015 cm3 |
(b) 1013 /cm3 |
(c) 1012 /cm3 |
(d) 1016 /cm3 |
A ray of light is incident at 50° on the middle of one of the two mirrors arranged at an angle of 60° between them. The ray then touches the second mirror, get reflected back to the first mirror, making an angle of incidence of
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(a) 50° |
(b) 60° |
(c) 70° |
(d) 80° |
Switch S of the circuit shown in figure. is closed at t = 0. If e denotes the induced
emf in L and i, the current flowing through the circuit at time t, which of the following graphs is correct
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(a)
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(b)
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(c)
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(d)
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