Question

Calculate the final flux in an inductor having inductance 4000 H, number of turns is 200 and the current changes from 5A to 7A. The initial flux is 760 Wb.

(a) 200 Wb

(b) 400 Wb

(c) 600 Wb

(d) 800 Wb

I got this question in examination.

I need to ask this question from Ferromagnetic Cored Inductor in a DC Circuit in division Inductance in a DC Circuit of Basic Electrical Engineering

Answer 1

Right option is (d) 800 Wb

Easiest explanation: From the formula of incremental inductance, we know that:

L=(Change in flux/Change in current)*Number of turns

Substituting the values from the given question, we get a change in flux = 40 Wb.

Change in flux = final flux- initial flux.

Thus final flux = 800 Wb.