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प्रश्न
A variable frequency a.c source is connected to a capacitor. How will the displacement current change with decrease in frequency?
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उत्तर
Capacitive reaction `X_C = 1/(2pi fC)`
Hence, `X_C oo 1/f`
As frequency decreases, `X_C` increases and the conduction current is inversely proportional to `X_C (because I oo 1/(X_C))`.
It means the displacement current decreases as the conduction current is equal to the displacement current.
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