In 5 minutes, a current of 5 amps is established in a wire. How many coulombs and how many electrons pass through each cross section of this wire?
The current is
"\\displaystyle I = \\frac{q}{t} \\; \\Longrightarrow \\; q = It"
"q = 5 A \\cdot5 \\cdot 60 s = 1500\\,C"
One electron has charge "1.6 \\cdot 10^{-19} \\, C". Then
"\\displaystyle N = \\frac{q}{1.6 \\cdot 10^{-19}} = \\frac{1500}{1.6 \\cdot 10^{-19}} = 937.5 \\cdot 10^{19} = 9.375 \\cdot 10^{21}"
Answer: "1500\\; C, \\, 9.375 \\cdot 10^{21}"
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