JEE Main2016PhysicsCurrent ElectricityActual
A galvanometer has a 50 division scale. Battery has no internal resistance. It is found that there is deflection of 40 divisions when R.B. = 2400 Ω . Deflection becomes 20 divisions when resistance taken from resistance box is 4900 Ω. Then we can conclude : Note: This question is awarded as the bonus. Now the question is corrected.
Options
- ACurrent sensitivity of galvanometer is 20 μ A / d i v i s i o n
- BResistance of galvanometer is 200 Ω .
- CResistance required on R.B. for a deflection of 10 divisions is 9800 Ω .
- DFull scale deflection current is 2 mA.
Correct answer
A. Current sensitivity of galvanometer is 20 μ A / d i v i s i o n
Step-by-step solution
Current in the circuit, I = V 2400 + R G and I 2 = V 4900 + R G ⇒ R G = 100 Ω I = 2 2500 = 8 × 10 - 4 A Current Sensitivity = 8 × 10 - 4 40 20 μ A per division