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Question : 18
Total: 26
State the principle of working of a galvanometer. A galvanometer of resistance G V R 1 R 2
R 1 R 2 2 V G R 1 R 2
Solution:
Working Principle
Finding the required resistance
Finding the resistanceG
Working Principle: A current carrying coil experiences a torque when placed in a magnetic field which tends to rotate the coil and produces an angular deflection.
V = I g ( G + R 1 )
= I g ( G + R 2 )
⇒ 2 =
⇒ G = R 1 − 2 R 2
LetR 3 2 V
∴ 2 V = I g ( G + R 3 )
Also V = I g ( G + R 1 )
∴ 2 =
∴ R 3 = G + 2 R 1
= R 1 − 2 R 2 + 2 R 1
= 3 R 1 − 2 R 2
Finding the required resistance
Finding the resistance
Working Principle: A current carrying coil experiences a torque when placed in a magnetic field which tends to rotate the coil and produces an angular deflection.
Let
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