COMEDK · Physics · 19. Current Electricity
A galvanometer of resistance \(50 \Omega\) is connected to a battery of 4 V along with a resistance of \(3950 \Omega\) in series. A full-scale deflection of 30 divisions is obtained in the galvanometer. In order to reduce this deflection to 10 divisions, the resistance in series should be equal to:
- A 6000 ohm
- B 8950 ohm
- C 7000 ohm
- D 11950 ohm
Answer & Solution
Correct Answer
(D) 11950 ohm
Step-by-step Solution
Detailed explanation
The current \(I\) flowing through the galvanometer for a full-scale deflection of \(30\) divisions is given by Ohm's law: \(I = \dfrac{V}{R_{g} + R_{s}} = \dfrac{4}{50 + 3950} = \dfrac{4}{4000} = 10^{-3} \text{ A}\) The current per division is…
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