Physics
A battery of e.m.f. 6.0 V supplies current through a circuit in which resistance can be changed. A high resistance voltmeter is connected across the battery. When the current is 3 A, the voltmeter reads 5.4 V. Find the internal resistance of the battery.
Current Electricity
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Answer
Given,
e.m.f. (ε) = 6.0 V
Current (I) = 3 A
Potential difference (V) = 5.4 V
r = ?
From relation,
V = ε – Ir
Substituting the values in the formula above we get,
Hence, internal resistance of the battery = 0.2 Ω
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