Question

question physics class 12 dc Circuit and measurment​

Answer 1

Answer:

2.1V

Explanation:

BC = 70cm

AB = 100cm

Therefore, AC = 30cm.

Now,

Potential difference across AB = 3V

i.e., For a length of 100cm, pot. diff. = 3V

=> For every 1cm length, pot. diff. = 3/100 = 0.03V/cm

Therefore, Potential Gradient = 0.03V/cm

So,

Potential drop across BC = (Potential Gradient) × (Length)

= (0.03 × 70) V = 2.1 V

Thus, reading in voltmeter will be 2.1V