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प्रश्न
State the principle of the working of a moving coil galvanometer, giving its labeled diagram ?
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उत्तर
Moving coil Galvanometer
Principle:
Its working is based on the fact that when a current carrying coil is placed in a magnetic field, it experiences a torque.
Working:
Suppose the coil PQRS is suspended freely in the magnetic field.
Let
l = Length PQ or RS of the coil
b = Breadth QR or SP of the coil
n = Number of turns in the coil
Area of each turn of the coil, A = l × b
Let B = Strength of the magnetic field in which coil is suspended
I = Current passing through the coil in the direction PQRS
Let, at any instant, α be the angle which the normal drawn on the plane of the coil makes with the direction of magnetic field.
The rectangular coil carrying current when placed in the magnetic field experiences a torque whose magnitude is given by,
τ = nIBA sin α
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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.
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.
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