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Question
An electric heater is connected to the 230 V mains supply. A current of 8 A flows through the heater.
- How much charge flows around the circuit each second?
- How much energy is transferred to the heater each second?
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Solution
Given: Potential difference = 230 V
Current (I) = 8 A
a. I = `Q/t``
⇒ 8 = Q/1
⇒ Q = 8 × 1
⇒ Q = 8C
Therefore, the charge that flows around the circuit every second is 8 C.
b. We know that,
Energy transferred = Work done
Potential difference = `"Work done"/"Charge moved"`
⇒ 230 = `"Work done"/8`
⇒ Work done = 230 × 8
⇒ Work done = 1840 J
Thus, 1840 joules of energy are transferred to the heater each second.
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