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JEEPhysicsAlternating CurrentClass 12

What does “Reactance” actually mean in Alternating Current, and why does it matter for JEE?

the opposition a capacitor (Xc = 1/ωC) or inductor (XL = ωL) offers to AC — frequency-dependent, unlike resistance.

In simple words: the opposition a capacitor (Xc = 1/ωC) or inductor (XL = ωL) offers to AC — frequency-dependent, unlike resistance. Getting Reactance clear matters because JEE questions on Alternating Current usually test this idea directly, not just a formula you memorised.

Key point

Reactance

Common mistake

treating reactance as a fixed resistance.

Memory tip

reactance changes with frequency; resistance doesn't.

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