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Question
In 10 s, a charge of 25 C leaves a battery, and 200 J of energy are delivered to an outside circuit as a result.
- What is the p.d. across the battery?
- What current flows from the battery?
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Solution
Given: Time (t) = 10 s
Charge (Q) = 25 C
Energy delivered is work done (W) = 200 J
a. Using the relation,
Potential difference = `"Work done"/"Charged moved"`
V = `W/Q`
V = `200/25`
V = 8 V
∴ So the p.d. across the battery is 8 volts.
b. Current = `"Charge"/"Time"`
I = `Q/t`
I = `25/10`
I = 2.5 A
∴ So, a current of 2.5 A flows from the battery.
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