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Assertion: An electric lamp connected in...

Assertion: An electric lamp connected in series with a variable capacitor and `AC` source, its brightness increases with increases in capacitance.
Reason: Capacitive reactance decrease with increases in capacitance of capacitor.

A

If both the assertion and reason are true and reason is a true explantion of the assertion.

B

If both the assertion and reason are true but the reason is not true the correct explantion of the assertion.

C

If the assertion is true but reason false

D

If both the assertion and reason are false.

Text Solution

Verified by Experts

The correct Answer is:
A

Capacitance reactance `X_(C)=1/(omegaC)`. When capacitance `(C)` increases, the capacitive reactance decreases. Due to decreases in its values, the current in the circuit will increases `(I=E/(sqrt(R^(2)+X_(C)^(2))))` and hence brightness of source (or electric lamb) will also increases.
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