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(i) Does not obey ohm's law. current is not directly proportional to voltage.
(ii) (I) at I = 1.5 A, R = gradient of tangent at I = $\frac{9.2 - 4.8}{3.6 - 0.1}$ = 1.26 ohms
(II) at I = 3.5 A, R = gradient of tangent at I = $\frac{9.4- 7.2}{5.4 - 1.5}$ = 0.56 ohms
johnmulu answered the question on May 23, 2017 at 13:03
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