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NEETPhysicsAlternating CurrentClass 12

I keep getting “Reactance” questions wrong in Alternating Current. What's the trap?

treating reactance as a fixed resistance.

The usual trap: treating reactance as a fixed resistance. How to avoid it: reactance changes with frequency; resistance doesn't. Go back to the definition — the opposition a capacitor (Xc = 1/ωC) or inductor (XL = ωL) offers to AC — frequency-dependent, unlike resistance.

Key point

Reactance

Common mistake

treating reactance as a fixed resistance.

Memory tip

reactance changes with frequency; resistance doesn't.

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