AL Physics current

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At joint A, by Kirchoff's 1st law, I1 + I2 + I3 = 0

Since I3 = 0, I1 = -I2 ... (1)

Consider the loop AB through the 6V battery,

By Kirchoff's 2nd law,

6 - I2(5) + I1(10) = 0

6 - 5I2 + 10I1 = 0

6 - 5I2 - 10I2 = 0 (By (1))

I2 = 0.4 A

Consider the loop AB through the 2V battery, let V be the potential across the voltmeter (reading)

By Kirchoff's 2nd law,

2 - 5I2 + V = 0

2 - 5(0.4) + V = 0

V = 0

The answer is A.