# Cr and lr circuits help exam in a bit and i'm stuck

1. Mar 31, 2008

### frixis

cr and lr circuits help.. exam in a bit and i'm stuck!!!

okay so here's my question :
how is the peak voltage across the resistance (in a cr circuit) or the induction (in an rl circuit) = $$\pm$$V$$_{m}$$/(1-e$$^{-T/2\tau}$$)

V$$_{m}$$ is the max voltage of the pulse train.
the m denotes max

both circuits are in a steady state with a pulse response

if it were a positive step then v=V$$_{m}$$e$$^{-T/\tau}$$
and if it were a negative step it would be v=-V$$_{m}$$e$$^{-T/\tau}$$

so from this i can gather that the peak values will be a plus minus thing..
i can get to peak voltage = V$$_{m}$$-v
but apart from that i'm very very lost... i've been working on this for a long while now but...