A 1.5 V battery produces 41.8 mA when it is across a 30.0 Ω load. The potential difference across the battery's terminals is

Explanation:

V = I R

V = 0.0418 * 30

V = 1.254

this battery seems dead  :P

Explanation:

Let's just assume that the battery has no internal  resistance. If we get an absurd answer, we'll come back and look at that assumption.

E = I * R

I = 41.8/1000 amps = 0.0418

R = 30.0 ohms

E = 0.0418 * 30

E = 1.254 volts. This is an OK answer. The battery is a little old.

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