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प्रश्न
The combined resistance of a galvanometer of resistance 500Ω and its shunt is 21Ω. Calculate the value of shunt.
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उत्तर
Here, G = 500Ω and Req = 21Ω
`1/R_(eq)=1/G+1/S`
`therefore 1/S=1/R_(eq)-1/G=(G-R_(eq))/(GxxR_(eq)`
`therefore S=(GxxR_(eq))/(G-R_(eq)`
`therefore S=(500xx21)/(500-21)=10500/479`
`therefore S= 21.92 Omega`
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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.
Write the underlying principle of a moving coil galvanometer.
Why does a galvanometer show a momentary deflection at the time of charging or discharging a capacitor? Write the necessary expression to explain this observation.
Increasing the current sensitivity of a galvanometer may not necessarily increase its voltage sensitivity. Explain, giving reason.
Two moving coil meters, M1 and M2 have the following particulars:
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.)
Determine the ratio of
- current sensitivity and
- voltage sensitivity of M2 and M1.
Explain how moving coil galvanometer is converted into a voltmeter. Derive the necessary formula.
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a) `S/(S+G)`
b) `G/(S+G)`
c) `(S+G)/G`
d) `(S+G)/S`
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How will you convert a moving coil galvanometer into a voltmeter?
Define current sensitivity of a galvanometer.
Why does a galvanometer when connected in series with a capacitor show a momentary deflection, when it is being charged or discharged?
How does this observation lead to modifying the Ampere's circuital law?
Hence write the generalised expression of Ampere's law.
Define the current sensitivity of a galvanometer ?
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Reason: A circular coil produces a uniform magnetic field around itself when an electric current is passed through it.
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Voltage sensitivity of a galvanometer is defined as the:
The current sensitivity of a moving coil galvanometer is given by:
The unit in which the current sensitivity of a galvanometer is expressed is:
The unit of voltage sensitivity of a galvanometer is:
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