(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Maximum current:

I max = 4.62 * 10^-4 A

Time constant of circuit:

T = 3.9 seconds

2. Relevant equations

T= RC

3. The attempt at a solution

I'm trying to find the current after 1 time constant. Seems simple enough, the current changes by 63%. So (Imax)-(Imax * 0.63) or basically I max * 0.37

But the teacher just took I max * 0.63 !!! I thought it CHANGES by 63% not simply 63% of the original value!!

I looked it up and all websites agree that the current after 1 time constant will be 0.37 of it's maximum value, hence a change of 63%!

http://www.electronics-tutorials.ws/rc/rc_1.html

Has the teacher made a mistake? I have deeply confused myself over a simple thought. Please help.

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# Homework Help: Current after (1) time constant in RC circuits

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