{{tag>charges ballon chapter1_2}}
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<WRAP mexle-task-title>
~~#@ee1_taskctr~~ Charges on a Ballon                   
</WRAP>

   

A balloon has a charge of $Q=7~{\rm nC}$ on its surface. \\ 
How many additional electrons are on the balloon?


<button size="xs" type="link" collapse="mexle-7f67e7d9d20d-1">Solution steps</button>
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\begin{align*}
Q         &=   7~{\rm nC} = 7\cdot 10^{-9}~{\rm C} \\
n_{\rm e} &= {{7*10^{-9}~{\rm C}}\over{1.6022*10^{-19}~{\rm C/electron}}} 
           = 43.7*10^{9}~{\rm electrons}
\end{align*}

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<button size="xs" type="link" collapse="mexle-7f67e7d9d20d-2">Result</button>
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\begin{align*}
43.7*10^{9}~{\rm electrons} 
\end{align*}

</collapse>




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