Two sources of current of equal emf are connected in series and have different…

PHYSICS · Subjective · A Level · Physics · Electricity · Electricity

Problem

Two sources of current of equal emf are connected in series and have different internal resistances

r_1

and

r_2

, where

r_2>r_1

. Find the external resistance

r

at which the potential difference across the terminals of one of the sources becomes zero.