A $4 Ω$ coil and a $2 Ω$ coil are connected in parallel. What is their combined resistance? A total current of 3A passes through the coils. What current passes through the $2 Ω$ coil?
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$4\Omega$ and $2\Omega$ coil are connected in parallel.
Combined resistance is R
$\frac{1}{\text{R}}=\frac{1}{4}+\frac{1}{2}=\frac{3}{4}$
$\text{R}=\frac{4}{3}\Omega$
Total current $\text{I}=\frac{\text{V}}{\text{R}}=3\Omega$
$\frac{\text{V}}{\frac{4}{3}}=3$
$\text{V}=3\times\frac{4}{3}=4\text{V}$
Current through $2\Omega$ coil $=\frac{\text{V}}{2}=\frac{4}{2}=2\text{A}$
Combined resistance is R
$\frac{1}{\text{R}}=\frac{1}{4}+\frac{1}{2}=\frac{3}{4}$
$\text{R}=\frac{4}{3}\Omega$
Total current $\text{I}=\frac{\text{V}}{\text{R}}=3\Omega$
$\frac{\text{V}}{\frac{4}{3}}=3$
$\text{V}=3\times\frac{4}{3}=4\text{V}$
Current through $2\Omega$ coil $=\frac{\text{V}}{2}=\frac{4}{2}=2\text{A}$
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