MHT CET202522 Apr 2025Morning ShiftPhysicsCurrent ElectricityActual
In the given electrical network, the value of resistance ' R ' when the current in the galvanometer will be zero, is
Options
- A4
- B6
- C7
- D10
Correct answer
B. 6
Step-by-step solution
With no current through the galvanometer, the node labeled A has potential V_A = 6 V since the galvanometer connects to the 6 V battery's positive terminal. Currents leaving node A are through R and the 4 resistor: I_R = V_A R = 6 R I_ 4 = V_A - 10 4 = 6 - 10 4 = -1 A Applying KCL at node A : 6 R + (-1) = 0 6 R = 1 R = 6 The resistance is 6 , corresponding to option B.