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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.
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(A) low resistance
(b) high resistance
(C) infinite resistance
(D) zero resistance
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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
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- Would your answer change, if the circular coil in (a) were replaced by a planar coil of some irregular shape that encloses the same area? (All other particulars are also unaltered.)
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a) `S/(S+G)`
b) `G/(S+G)`
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Hence write the generalised expression of Ampere's law.
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Write current sensitivity of a galvanomete S.I. unit.
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Draw a labelled diagram of a moving coil galvanometer and explain its working. What is the function of radial magnetic field inside the coil?
In the meter bridge experiment, balance point was observed at J with AJ = l.
(i) The values of R and X were doubled and then interchanged. What would be the new position of balance point?
(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 ?
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State how a moving coil galvanometer can be converted into an ammeter.
A galvanometer coil has a resistance of 12 Ω and the metre shows full scale deflection for a current of 3 mA. How will you convert the metre into a voltmeter of range 0 to 18 V?
A galvanometer coil has a resistance of 15 Ω and the metre shows full scale deflection for a current of 4 mA. How will you convert the metre into an ammeter of range 0 to 6 A?
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In a moving coil galvanometer the deflection (Φ) on the scale by a pointer attached to the spring is ______.
A moving coil galvanometer can be converted into an ammeter by ______.
A galvanometer having a coil resistance of 60 Ω shows full-scale deflection when a current of 1.0 amp passes through it. It can be converted into an ammeter to read currents up to 5.0 amp by:
The coil of galvanometer consists of 100 turns and effective area of 1 square cm. The restoring couple is 10-8 N-m/rad. The magnetic field between the pole pieces is 5T. The current sensitivity of this galvanometer will be ______.
A multirange voltmeter can be constructed by using a galvanometer circuit as shown in figure. We want to construct a voltmeter that can measure 2V, 20V and 200V using a galvanometer of resistance 10Ω and that produces maximum deflection for current of 1 mA. Find R1, R2 and R3 that have to be used.

A voltmeter of variable ranges 3 V, 15 V, 150 V is to be designed by connecting resistances R1, R2, R3 in series with a galvanometer of resistance G = 20 Ω, as shown in Fig. The galvanometer gives full pass through its coil for 1 mA current i.e. "gives full pass through it's coil for 1 mA current". Then, the resistances R1, R2 and R3 (in kilo ohms) should be, respectively:

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Explain in brief the basic construction of a moving-coil table galvanometer whit a neat labelled diagram.
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A moving coil galvanometer of resistance 55 Ω produces a full scale deflection for a current of 250 mA. How will you convert it into an ammeter with a range of 0 - 3A?
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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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