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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
A moving coil galvanometer has a resistance of 25Ω and gives a full scale deflection for a current of 10mA. How will you convert it into a voltmeter having range 0 - 100 V?
Figure shows two circuits each having a galvanometer and a battery of 3V.
When the galvanometers in each arrangement do not show any deflection, obtain the ratio R1/R2.
In the meter bridge experiment, balance point was observed at J with AJ = l.
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(ii) If the galvanometer and battery are interchanged at the balance position, how will the alance point get affected?
Define the term ‘current sensitivity’ of a moving coil galvanometer.
A galvanometer of resistance 100 Ω gives a full-scale deflection for a current of 10−5 A. To convert it into an ammeter capable of measuring up to 1 A we should connect a resistance of ______.
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.
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A voltmeter has a range of 0 - 20 V and a resistance of 500 Q. Explain how can be used to measure voltages from 0 - 200 volt?
A galvanometer of resistance 100 Ω gives a full-scale deflection for a potential difference of 200 mV.
- What must be the resistance connected to convert the galvanometer into an ammeter of the range 0-200 mA?
- Determine resistance of the ammeter.
