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#@TaskTitle_HTML@##@Lvl_HTML@#~~#@ee1_taskctr#~~  Electron flow                   #@TaskText_HTML@#   

How many electrons pass through a control cross-section of a metallic conductor when the current of $40~{\rm mA}$ flows for $4.5~{\rm s}$?

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\begin{align*}
Q &= I \cdot t                      \\
  &= 0.04~{\rm A} \cdot 4.5~{\rm s} \\
  &= 0.18~{\rm As}                  \\
  &= 0.18~{\rm C} \\
  &={0.18~{\rm C}}\cdot {1\over{1.6022*10^{-19}{\rm C/electron}}} = 1.1 \cdot10^{18}~{\rm electrons} 
\end{align*}


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#@ResultBegin_HTML~1~@#
\begin{align*}
1.1*10^{18}~{\rm electrons} 
\end{align*}
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