A sensitive galvanometer gives full-scale deflection with 100 mV. If the resistance of the galvanometer is 50? the maximum current that can flow through safely is__________________?
Correct answer: A. 2.0 mA
- A. 2.0 mA
- B. 20 mA
- C. 200 mA
- D. 0.2 mA
Explanation
Using I = V/R, the maximum safe current is I = 100 mV / 50 Ω = 0.100 V / 50 Ω = 0.002 A = 2.0 mA. Students may choose d, 0.2 mA, by mishandling the conversion from millivolts to volts or the division by 50 Ω.
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