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Question
A bulb is connected to a battery of p.d. 4 V and internal resistance 2.5 Ω . A steady current of 0.5 A flows through the circuit. Calculate:
The resistance of the bulb
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Solution
Given ,
Voltage , V = 4 V
Resistance of the battery , RB = 2.5 Ω
Current , I = 0.5 A
Total resistance , R = 8 Ω
Resistance of the battery , RB = 2.5 Ω
Resistance of the blub, Rb = 8 - 2.5 Ω = 5.5 Ω
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