How Do You Calculate Charge and Current Over Time in a Defibrillator Circuit?

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The discussion revolves around calculating charge (q) and current (I) over time in a defibrillator circuit using the equations q(t) = Q(1-e^(-t/RC)) and I(t) = (emf/R)e^(-t/RC). The user encountered issues with WebAssign rejecting their answers, despite believing their calculations were correct. Suggestions include ensuring that units are included in the expressions for q and I, particularly the time constant of 1.7 seconds. There is also a note that slight variations in numerical results may occur. Clarity on syntax and unit inclusion is crucial for accurate submissions.
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**EDIT: I solved the second part of the problem, I just need help on the syntax for the 2 equations of q(t) and I(t).

Homework Statement



http://img262.imageshack.us/img262/2139/phys1xf8.jpg

Homework Equations



First Part:
q(t) = Q(1-e-t/RC)
I(t) = (emf/R) e-t/RC

The Attempt at a Solution


For the equations of q and I as functions of time, I basically plugged in all the numbers and WebAssign is telling me that it's wrong. I'm not sure what I'm doing wrong -- any help would be appreciated.

Please help. :(
 
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Just a guess, but they might want you to include units in your expressions for q and I, including the 1.7s in the exponential. They had provided the units in the previous answers, but not for those.

Your numbers for q and I look right to me. I get something slightly different for (a).
 

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