# Electronics - Inductors - Discussion

### Discussion :: Inductors - General Questions (Q.No.57)

57.

What is the current rise after 2 time constants if Vs = 12 V dc, R = 60 , and the inductor is rated at 24 mH?

 [A]. 79.9 mA [B]. 126.4 mA [C]. 173.0 mA [D]. 198.6 mA

Explanation:

No answer description available for this question.

 Chaitali Acharya said: (Dec 2, 2011) Please could anyone give a formula for this question?

 Prasanna said: (Aug 20, 2012) R + jXL= sqrt( 60^2 + 24^2 ) I = Vs/(R+ jXL) 2t=.862 I at 2t is = I*0.862

 Sajid said: (Oct 13, 2012) I = It*(e^(-2)) It=Vs/Z Z=(R^2+Xl^2)^1/2 Xl=2*3.14*f*L /// f=0,Since DC /// Z = R It = Vs/R =12/60 =.2 Now, I = .2(e^(-2)) = .1729 =173mA

 Sanjoy said: (Feb 29, 2016) Current rise after 2 time constant. So, IL = I(1-e^-2). IL = 0.2 (1-0.13) = 173 mA.

 Sivapramod said: (Jul 17, 2016) What is the value of 'e' in the given formula?

 E.Sae said: (Dec 25, 2016) @Sivapramod. e means exponential

 E.Sae said: (Dec 25, 2016) @Sivapramod. e means exponential