What is the Equation for Current as a Function of Time in a Circuit?

Thread starter jst
Start date Feb 14, 2007
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Current Function Time

AI Thread Summary

The equation for charge passing through a circuit is given as q = 3t^3 – t^2. To find the current as a function of time, the derivative of the charge equation with respect to time is taken. The correct expression for current, denoted as q', is 9t^2 - 2t. This method of differentiation is confirmed as the appropriate approach to determine current in this context. Understanding this relationship is crucial for analyzing circuit behavior over time.

Feb 14, 2007

jst

Homework Statement

Given an equation for charge passing through a point in a circuit versus time: q = 3t^3 – t^2. Which is the correct equation for current as a function of time?

Homework Equations

The Attempt at a Solution

Would it be: q', which would be 9t^2 - 2t

Thanks a lot,

Jason

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Feb 14, 2007

imastud

yeah that's right you take the derivitive of q(t) with respect to t

Feb 14, 2007

jst

Much thanks!

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