V1=ϵ1−i.r1
0=10−i×20
i=0.5A
V2=307.5+x7.5
0.5=0.25+x7.5
x7.5=0.25x=0.257.5=30Ω
JEE Main 2020 — Physics Electromagnetism
The series combination of two batteries, both of the same emf 10V, but different internal resistance of 20Ω and 5Ω, is connected to the parallel combination of two resistors 30Ω and x Ω. The voltage difference across the battery of internal resistance 20Ω is zero, the value of x (in Ω) is____
Held on 8 Jan 2020 · Verified 6 Jul 2026.
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