A moving coil galvanometer of resistance 100? gives half scale deflection for a current of 20mA. What will be the potential difference across it ?
Correct answer: C. 2 volt
- A. 4 volt
- B. 5 volt
- C. 2 volt
- D. 0.4 volt
Explanation
Using Ohm's law, the potential difference is V = IR = (0.020 A)(100 Ω) = 2.0 V. The half-scale deflection does not alter this calculation because the stated current is the current through the galvanometer. The likely wrong choice is d, caused by treating 20 mA as 0.20 A instead of 0.020 A.
Last updated
About Steady Current
Steady current is the continuous flow of charge at a constant rate through a conductor. The topic covers current, charge, potential difference, resistance, Ohm's law, resistivity and electrical power, along with series and parallel circuits, while distinguishing conventional current direction from electron motion.
Practise Current Electricity
1,052 free Current Electricity MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Physics questions like this
Physics is on 13 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
Related questions
2.00 x 10^6 e passing through a conductor in 1 millisecond. Electric current through conductor is:
A 0.01A moving coil Galvanometer of 5 Ω resistance can be converted into a 0.2A ammeter by a resistance R with the Galvanometer when r is:
A 1000 W lamp operates at 220 V for 60 s.The electric current passing through the lamp will be
A 3 V battery is connected in series with ammeter and 2 ohm resistance after short circuiting. What will be the reading of ammeter?
a battery of 12 volts is connected to three resistors of 4 ohm, 5 ohm and 3 ohm joined together in parallel, the current through 3 ohm resistor would be?