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Question
Define capacitive reactance. Give its units.
Solution
The peak value of current I is given by Im = `"v"_"m"/(1//"c"_omega)`. Let us compare this equation with Im = `"V"_"m"/"R"` from resistive circuit. The quantity `1/(omega"C")` plays the same role as the resistance R in resistive circuit. This is the resistance offered by the capacitor, called capacitive reactance (XC). It measured in ohm.
XC = `1/(omega"C")`.
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