# Physics

A battery has an unknown e.m.f, ε,and an internal resistance r = 0.40Ω. When a resistance R = 5.60Ω is connected across the terminals of the battery, the terminal potential difference across the battery is 11.2V. What is the e.m.f. of the battery?

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1. Hey , try yourself this time and Henry or I or someone will check.

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2. I = V/R = 11.2/5.6 = 2A.
e.m.f. = I * (r+R) = 2 * (0.4+5.6) =

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