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If frequency of alternating source is ma...

If frequency of alternating source is made zero then which of the following statement is true-

A

current through capacitor will be zero

B

current through resistance will be zero

C

current through inductance will be zero

D

all

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to analyze the behavior of current through a capacitor, resistor, and inductor when the frequency of the alternating source approaches zero. ### Step-by-Step Solution: 1. **Understanding the AC Source**: The alternating source can be represented as: \[ E = E_0 \sin(\omega t) \] where \(\omega = 2\pi f\) and \(f\) is the frequency. **Hint**: Remember that \(\omega\) is directly proportional to frequency \(f\). 2. **Current through the Inductor**: The current through an inductor \(I_L\) is given by: \[ I_L = \frac{E}{X_L} = \frac{E_0}{\omega L} \] where \(X_L\) is the inductive reactance. **Hint**: Reactance depends on frequency; as frequency approaches zero, observe what happens to \(X_L\). 3. **Current through the Capacitor**: The current through a capacitor \(I_C\) is given by: \[ I_C = \frac{E}{X_C} = E \cdot \omega C \] where \(X_C = \frac{1}{\omega C}\) is the capacitive reactance. **Hint**: Capacitive current is directly proportional to frequency; consider what happens when frequency is zero. 4. **Current through the Resistor**: The current through a resistor \(I_R\) is given by: \[ I_R = \frac{E}{R} \] The resistance \(R\) does not depend on frequency. **Hint**: Resistor current remains constant regardless of frequency changes. 5. **Setting Frequency to Zero**: If the frequency \(f\) is made zero, then: - \(\omega = 2\pi f = 0\) - For the inductor: \[ I_L = \frac{E_0}{0} \rightarrow \text{undefined (approaches infinity)} \] - For the capacitor: \[ I_C = E \cdot 0 = 0 \] - For the resistor: \[ I_R = \frac{E}{R} \text{ (remains finite)} \] **Hint**: Analyze the implications of \(\omega\) being zero on each component. 6. **Conclusion**: - Current through the capacitor \(I_C\) will be zero. - Current through the resistor \(I_R\) will not be zero. - Current through the inductor \(I_L\) will be undefined (or infinite). - Therefore, the only true statement is that the current through the capacitor will be zero. **Final Answer**: The correct option is **A**: Current through the capacitor will be zero.
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