19 lines
776 B
Markdown
19 lines
776 B
Markdown
---
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categories:
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- Electronics
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tags: [physics, electricity]
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---
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# Current
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When an appropriate external force is applied, the movement of electrons is from negatively charged atoms (negative ions) to positively charged atoms (positive ions). We call this **electrical current**.
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We use the symbol $I$ to stand for current in equations.
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> The amount of current is the sum of the charges of the moving electrons past a given point.
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## Coulombs and amps
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We measure **charge** in Coulombs ($C$). A Coulomb is an aggregate of the charge of several electrons because their charge is so small: $6.24 \cdot 10 ^{18}$ electrons.
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We measure **current** in amps. When one coulomb of charge moves past a point in one second it is called an **ampere** (amp) represented as $A$.
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