Calculating Total Charge Flowing Through Circuit

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The discussion focuses on calculating the total charge flowing through a circuit where the current decreases linearly from 5A to 1A over 4 hours. The formula used integrates the current function over time, resulting in a total charge of 43,200 coulombs. Participants express surprise at the large amount of charge, questioning if the calculation is correct given the long duration and the final current value. However, the calculations appear accurate, confirming the results. The conclusion emphasizes that the large charge is consistent with the extended time period of current flow.
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In this problem assume that current is linearly proportional to time. The intial condition at time 0 is 5A. At time 4 hours the current is 1A. What is the total charge that flows through this circuit?

t_0=0
i_0=5A
t_f=14400s
i_f=1A

\frac{i_f-i_0}{t_f-t_0} =\frac{-4A}{14400}

q=\int_{0}^{14400}(\frac{-1A}{3600}t+5)dt

q= \left[\frac{-1}{7200}t^2+5t\right]_{0}^{14400}

q= 43200C

That seems like a whole lot of charge. I know it is a long period of time. Can anyone see anything wrong with this?
 
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1A is a very large current too. It looks fine to me.
 
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