NEET 2018 · PhysicsGalvanometer sensitivityPrevious Year Question
Current sensitivity of a moving coil galvanometer is 5 div/mA and its voltage sensitivity (angular deflection per unit voltage applied) is 20 div/V. The resistance of the galvanometer is:
Answer: (A) 250 Ω. Answer: (A) Solution: Current sensitivity Sɪ = NBA/C; voltage sensitivity S_V = NBA/(CR) = Sɪ/R.
- A.250 Ω✓
- B.25 Ω
- C.40 Ω
- D.500 Ω
Correct Answer
(A) 250 Ω
Solution & Explanation
Answer: (A) Solution: Current sensitivity Sɪ = NBA/C; voltage sensitivity S_V = NBA/(CR) = Sɪ/R. So R = Sɪ/S_V = (5 div/mA)/(20 div/V) = (5 div / 10⁻³ A)/(20 div/V) = 5000/20 = 250 Ω. → option A.
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