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Question
A dry cell can supply a charge of 800 C. If continuous current of 8.0 mA is drawn, calculate the time in which cells will discharge completely.
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Solution
Charge = Q = 800 C
Electric current = I = 8.0 mA
I = 8 × 10-3 A
Time = t = ?
I = `"Q"/"t"`
t = `"Q"/"I"`
t = `800/(8 xx 10^-3) = 100 xx 10^3`
t = 100000 s
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