(i) e.m.f. = 2.1 V
(ii) E = V + Ir
2.1 = 1.8 + 0.1 r
0.3 = 0.1 r
r = 3 ohms
(iii) R = $\frac{V}{I}$ = $\frac{2.5}{0.1}$ = 18 ohms
johnmulu answered the question on May 23, 2017 at 11:37
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