Question: A unknown resistance is measured by substitution method. First a standard known resistance of 100 Ω is connected in series with a circuit having a rheostat and a galvanometer. The battery voltage is 10V and the setting of rheostat is 500 Ω and the galvanometer shows a deflection of 60°. After this test. The battery voltage goes down to 9 V and when the unknown resistance is substituted for the known resistance, the galvanometer again shows a deflection of 60° with the same setting of the rheostat. The value of unknown resistance is :
Answer:
MCQ: A unknown resistance is measured by substitution method. First a standard known resistance of 100 Ω is connected in series with a circuit having a rheostat and a galvanometer. The battery voltage is 10V and the setting of rheostat is 500 Ω and the galvanometer shows a deflection of 60°. After this test. The battery voltage goes down to 9 V and when the unknown resistance is substituted for the known resistance, the galvanometer again shows a deflection of 60° with the same setting of the rheostat. The value of unknown resistance is :
Correct Answer:
A. 100 Ω
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Related Questions
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