EASY
12th ICSE
IMPORTANT
Earn 100

Draw a labelled graph showing the variation of capacitive reactance (XC) Versus frequency f.

Important Questions on Alternating Current

MEDIUM
12th ICSE
IMPORTANT

In Fig. (a), (b) and (c) are shown three AC circuits with equal currents. If the frequency of emf be increased, then what will be the effect on the currents in these? Explain with reasons.

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MEDIUM
12th ICSE
IMPORTANT

In Fig. (a), (b) and (c) are shown three AC circuits with equal currents. If the frequency of emf be increased, then what will be the effect on the currents in these? Explain with reasons.

Question Image

MEDIUM
12th ICSE
IMPORTANT

In Fig. (a), (b) and (c) are shown three AC circuits with equal currents. If the frequency of emf be increased, then what will be the effect on the currents in these? Explain with reasons.

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EASY
12th ICSE
IMPORTANT
What if the choke coil and the bulb are connected to an AC source?
EASY
12th ICSE
IMPORTANT
A radio-frequency choke is air-cored coil whereas audio-frequency choke is iron-cored. Why?
EASY
12th ICSE
IMPORTANT
When a capacitor is connected in series with a series L-R circuit, the AC flowing in the circuit increases. Explain.
EASY
12th ICSE
IMPORTANT
In an alternating-current circuit, a bulb becomes dim when a choke coil (L) is connected in series with it; why? If we also connect a variable capacitor (C) in series then, by adjusting the capacity of the capacitor, the intensity of the bulb can be increased to previous level. How is it possible?
MEDIUM
12th ICSE
IMPORTANT
A bulb is connected in series with a variable capacitor. Will the bulb glow when this combination is connected to a DC supply/an AC supply? What would happen in each case, if the capacitance is reduced?