Q. In the given figure when galvanometer shows no deflection current flowing through $5\Omega$ resistance will be
A) 0.5 A
B) 0.6 A
C) 1.5 A
D) 2.0 A
Explanation
(b) Let$\ i$ be the current through arm $ADC$. Then current through arm $ABC = (2.1 - i)$. As there is no deflection in the galvanometer, hence
$(20 + 5)i = (8 + 2)(2.1 - i)$
or $25i = 21 - 10i\ or\ 35i = 21$
or $i = 21/35 = 3/5 = 0.6\ A$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.