Q14 of 26 Page 1

(i) Define mutual inductance.

(ii) A pair of adjacent coils has a mutual inductance of 1.5 H. If the current in one coil changes from 0 to 20 A in 0.5 s, what is the change of flux linkage with the other coil?


(i) When parallel coil are attached or kept together and current flown in one coil induces voltage on the other, this phenomenon is known as mutual inductance.


(ii) The flux linkage change is 30H


Given


The mutual inductances induced in the coils are M = 1.5H, the current induced is I = 20A, the time required for the induction is 0.5 sec.


Formula Used


To find the change in flux linkage we use the formula of mutual inductance where, when parallel coil are attached or kept together and current flown in one coil induces voltage on the other



where


is the flux change, is the mutual inductance, is the current flowing in the coil.


(ii) The mutual inductances induced in the coils are M = 1.5H


The current induced is I = 20A


The time required for the induction is 0.5 sec


Using the formula for the mutual induction we get the change in flux as





Therefore, the flux linkage change is 30H.


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