Home
Class 12
PHYSICS
At a certain frequency omega(1), the rea...

At a certain frequency `omega_(1)`, the reactance of a certain capacitor equals that of a certain inductor. If the frequency is changed to`omega_(2) = 2omega_(1)`, the raito of reactance of the inductor to that of the capacitor is :

A

`4:1`

B

`sqrt2:1`

C

`1:2sqrt2`

D

`1:2`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to find the ratio of the reactance of the inductor (XL) to the reactance of the capacitor (XC) when the frequency is changed from ω1 to ω2 = 2ω1. ### Step-by-Step Solution: 1. **Understand the Reactance of Inductor and Capacitor**: - The reactance of an inductor (XL) is given by: \[ X_L = \omega L \] - The reactance of a capacitor (XC) is given by: \[ X_C = \frac{1}{\omega C} \] 2. **Initial Condition**: - At frequency ω1, it is given that: \[ X_L = X_C \] - Therefore, we can write: \[ \omega_1 L = \frac{1}{\omega_1 C} \] - Rearranging gives: \[ \omega_1^2 LC = 1 \quad \text{(1)} \] 3. **Change of Frequency**: - Now, we change the frequency to ω2 = 2ω1. We need to find the new reactances: \[ X_L' = \omega_2 L = 2\omega_1 L \] \[ X_C' = \frac{1}{\omega_2 C} = \frac{1}{2\omega_1 C} \] 4. **Calculate the Ratio of Reactances**: - Now, we find the ratio of the new reactance of the inductor to that of the capacitor: \[ \frac{X_L'}{X_C'} = \frac{2\omega_1 L}{\frac{1}{2\omega_1 C}} = 2\omega_1 L \cdot 2\omega_1 C = 4\omega_1^2 LC \] 5. **Substituting from Equation (1)**: - From equation (1), we know that: \[ \omega_1^2 LC = 1 \] - Therefore: \[ \frac{X_L'}{X_C'} = 4 \cdot 1 = 4 \] 6. **Final Answer**: - The ratio of the reactance of the inductor to that of the capacitor at frequency ω2 is: \[ \frac{X_L'}{X_C'} = 4 \] ### Conclusion: The ratio of the reactance of the inductor to that of the capacitor when the frequency is changed to ω2 = 2ω1 is **4**.
Promotional Banner

Similar Questions

Explore conceptually related problems

The reactance of a 25 muF capacitor at the AC frequency of 4000Hz is

An AC voltage source is applied across an R-C circuit. Angular frequency of the source is omega , resistance is R and capacitance is C. The current registered is I. If now the frequency of source is changed to omega/2 (but maintaining the same voltage), the current in the circuit is found to be two third. calculate the ratio of reactance to resistance at the original frequency omega .

When the frequency of the AC source in an LCR circuit equals the resonant frequency, the reactance of the circuit is zero. Does it mean that there is no current through the inductor or the capacitor?

An a.c. source of angular frequency omega is fed across a resistor R and a capacitor C in series. The current registered is I. If now the frequency of the source is changed to omega//3 (but maintaining the same voltage), the current in the circuit is found to be halved. calculate the ratio of reactance to resistance at the original frequency omega .

An AC source of frequency omega when fed into a RC series circuit, current is recorded to be l. If now frequency is changed to (omega)/(4) (keeping voltage same), the current is found to 1/2. The ratio of reactance to resistance at original frequency omega is

An ac source of angular frequency omega is fed across a resistor R and a capacitor C in series. The current registered is I. If now the freqency of source is chaged to (omega)//3 (but maintainging the same voltage), the current in the circuit is found to be halved. Calculate the ration of hte reactance to resistance at the original frequency omega .

A series combination of resistor (R), capacitor (C) is connected to an AC source of angular frequency omega . Keeping the voltage same, If the frequency is changed to Omega/3 , the current becomes half of the original current. Then, the ratio of the capacitance reactance and resistance at the former frequency is

Explain why the reactance provided by a capacitor to an alternating current decreases with increasing frequency.

The reactance of a capacitor of capacitance C is X. If both the frequency and capacitance be doubled, then new reactance will be (a) X (b) 2X (c) 4X (d) (X)/(4)

The current in 1Omega resistance and charge stored in the capacitor are