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Question
An alternating current generator has an internal resistance Rg and an internal reactance Xg. It is used to supply power to a passive load consisting of a resistance Rg and a reactance XL. For maximum power to be delivered from the generator to the load, the value of XL is equal to ______.
Options
zero
Xg
– Xg
Rg
Solution
An alternating current generator has an internal resistance Rg and an internal reactance Xg. It is used to supply power to a passive load consisting of a resistance Rg and a reactance XL. For maximum power to be delivered from the generator to the load, the value of XL is equal to `underline(- X_g)`.
Explanation:
For maximum power to be delivered from the generator (or internal reactance Xg) to the load (of reactance, XL),
⇒ XL + Xg = 0 .....(The total reactance must vanish)
⇒ XL= – Xg
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