Confused by powers of ten; new capacitor voltage problem

[sshoptaugh1991]

Greetings everyone!

Well, I thought I had the understanding, but something is making me think I do not.  I have yet another capacitor voltage example, but this is an example problem, not just an example with the solution written out.

From looking at the voltage graph in the textbook, I am able to figure out the voltage equation from 0 <= t <= 2ms, but when I proceed to the next interval, there is a problem, namely with the magnitude power.

Here is what I have done so far:

i(t) = [-10(10^-6) / 2(10^-3) ]t   from 0 <= t <= 2ms
rewritten as -5(10^-3)t

i(t) = -10   from 2ms <= t <= 4ms
i(t) = 0      from 4ms <= t <= 5ms
i(t) = -10   from 5ms <= t <= 10ms


v(t) = 1/(10^-9) [int(-5(10^-3)t] - 5   from 0 <= t <= 2ms
      = (10^9) [-2.5(10^-3) t^2] - 5
v(2ms) = -15 V  as expected

However, this is where I run into problems with order of magnitude with the exponents:
v(t) = (10^9) [int(-10)] - 15    from 2ms <= t <= 4ms
      = (10^9) [-10t + 10(0.002)] - 15
      = -10(10^9)t + 20(10^6) - 15
v(4ms) = -20000015     what???  It should come out to -35.  I am confused as to my order of magnitude screw up.

Anyone have any suggestions?

[sshoptaugh1991]

Nevermind everyone, I figured out where I went wrong.  For the second and fourth current equations, I kept writing out i(t) = -10, instead of -10(10^-6).  That is where my problem came from.  Those small, minute details.  Watch out for those, everyone.  They will certainly mess you up.