Three separate devices A, B and C have their potential difference V (in volts)…
PHYSICS · Subjective · CBSE · Physics · Current Electricity · Current Electricity
Problem
Three separate devices A, B and C have their potential difference V (in volts) related to current I (in amperes) as follows:
Device A: V=2I
Device B: V=1.5I+0.5I2
Device C: I=0.8V
Answer the following for the above devices:
(i) For each device, state whether or not it obeys Ohm’s law and give one reason for your answer.
(ii) Determine the resistance of device A when the current is 3A.
(iii) Calculate the instantaneous (dynamic) resistance of device B at I=2A.
(iv) Comment qualitatively on how the resistance of device C varies with increase in applied voltage.