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The Fraction of the Total Current Passing Through the Galvanometer is ............ . - Physics

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प्रश्न

The fraction of the total current passing through the galvanometer is ............ .

a) `S/(S+G)`

b) `G/(S+G)`

c) `(S+G)/G`

d) `(S+G)/S`

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उत्तर

a) `S/(S+G)`

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2015-2016 (July)

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संबंधित प्रश्न

The combined resistance of a galvanometer of resistance 500Ω and its shunt is 21Ω. Calculate the value of shunt.


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Write the underlying principle of a moving coil galvanometer.


 

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Obtain the expression for current sensitivity of moving coil galvanometer.


A circular coil of 250 turns and diameter 18 cm carries a current of 12A. What is the magnitude of magnetic moment associated with the coil?


A galvanometer of resistance G is converted into a voltmeter to measure upto V volts by connecting a resistance R1 in series with the coil. If a resistance R2 is connected in series with it, then it can measures upto V/2 volts. Find the resistance, in terms of R1 and R2, required to be connected to convert it into a voltmeter that can read upto 2 V. Also find the resistance G of the galvanometer in terms of R1 and R2


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R1 = 10 Ω, N1 = 30,

A1 = 3.6 × 10–3 m2, B1 = 0.25 T

R2 = 14 Ω, N2 = 42,

A2 = 1.8 × 10–3 m2, B2 = 0.50 T

(The spring constants are identical for the two meters).

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Explain how moving coil galvanometer is converted into a voltmeter. Derive the necessary formula.


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15 cm2. It is suspended in the radial magnetic field 0.03 T. The twist constant of suspension
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(ii) If the galvanometer and battery are interchanged at the balance position, how will the alance point get affected?


State the principle of the working of a moving coil galvanometer, giving its labeled diagram ?


What are the advantages of using soft iron as a core, instead of steel, in the coils of galvanometers?


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