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Question
A bulb is connected to a battery of e.m.f. 6V and internal resistance 2Ω A steady current of 0.5A flows through the bulb. Calculate the total energy supplied by the battery in 10 minutes.
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Solution
Given: E = 6V, r = 2Ω, i = 0.5A, t = 10 minute = 10 × 60s = 600s.
The total energy supplied by the battery = Eit
= 6 × 0.5 × 600 = 1800 J
RELATED QUESTIONS
The table below shows the current in three different electrical appliances when connected to the 240 V mains supply:
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| Lamp | 0.4 A |
| toaster | 4.8 A |
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