Question
Physics Question on Alternating Current
A capacitor of capacity C and reactance X if capacitance and frequency become double then
A
4X
B
X/2
C
X/4
D
2X
Answer
X/4
Explanation
Solution
The correct option is(C): X/4 The capacitive reactance is determined by the formula: X = 1 / (ωC) = 1 / (2πfC) Here,C represents the capacitance,f represents the frequency. Now, when both the frequency and capacitance are doubled: X' = 1 / [2π(2f)(2C)] = 1 / (4πfC) This simplifies to: X' = (1/4) * (1 / (2πfC)) = (1/4) * X = (X / 4)