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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 total energy supplied by the battery in 10 minutes
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Solution
Given ,
Voltage , V = 4 V
Resistance of the battery , RB = 2.5 Ω
Current , I = 0.5 A
Energy supplied by the battery , E = `"V"^2/"R"`
t = 10 × 60 = 600 sec
R = `"V"/"I" = 4/0.5 = 8 Omega`
E = `((4)^2 xx 600)/8 = 1200 "J"`
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Loudspeaker, Bar magnet/magnet, Electric motor, Microphone.
