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Current in an ac circuit is given by I= ...

Current in an ac circuit is given by `I= 3 sin omega t + 4 cos omega t, ` then

A

rms value of current is 5A.

B

mean value of this current in any one half period will be `(6//pi)`.

C

If voltage applied is `V=V_(m) sin omega t`, then the circuit may be containing resistance and capacitance only.

D

If voltage applied is `V=V_(m) sin omega t`, then the circuit may be contain resostamce and inductance only.

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To solve the problem, we need to analyze the given current equation in an AC circuit: \[ I = 3 \sin(\omega t) + 4 \cos(\omega t) \] We will find the peak current, RMS value, average current, and phase difference step by step. ### Step 1: Combine the Sine and Cosine Terms We can express the current in a single trigonometric function using the following identity: \[ I = R \sin(\omega t + \phi) \] Where \( R \) is the resultant amplitude and \( \phi \) is the phase angle. To find \( R \) and \( \phi \), we can use the following relationships: - \( R = \sqrt{A^2 + B^2} \) - \( \tan(\phi) = \frac{B}{A} \) Here, \( A = 3 \) and \( B = 4 \). ### Step 2: Calculate the Resultant Amplitude \( R \) Using the formula for \( R \): \[ R = \sqrt{3^2 + 4^2} = \sqrt{9 + 16} = \sqrt{25} = 5 \] ### Step 3: Calculate the Phase Angle \( \phi \) Using the tangent formula: \[ \tan(\phi) = \frac{4}{3} \] To find \( \phi \): \[ \phi = \tan^{-1}\left(\frac{4}{3}\right) \] ### Step 4: Calculate the RMS Value \( I_{RMS} \) The RMS value for an AC current is given by: \[ I_{RMS} = \frac{I_0}{\sqrt{2}} \] Where \( I_0 \) is the peak current (which we found to be \( R = 5 \)): \[ I_{RMS} = \frac{5}{\sqrt{2}} \, \text{A} \] ### Step 5: Calculate the Average Current \( I_{avg} \) The average current over one complete cycle is given by: \[ I_{avg} = \frac{I_0}{\pi} \] Substituting \( I_0 = 5 \): \[ I_{avg} = \frac{5}{\pi} \, \text{A} \] ### Step 6: Determine the Phase Difference \( \phi \) From our earlier calculation, we have: \[ \phi = \tan^{-1}\left(\frac{4}{3}\right) \approx 53^\circ \] ### Summary of Results - Peak Current \( I_0 = 5 \, \text{A} \) - RMS Current \( I_{RMS} = \frac{5}{\sqrt{2}} \, \text{A} \) - Average Current \( I_{avg} = \frac{5}{\pi} \, \text{A} \) - Phase Difference \( \phi \approx 53^\circ \)

To solve the problem, we need to analyze the given current equation in an AC circuit: \[ I = 3 \sin(\omega t) + 4 \cos(\omega t) \] We will find the peak current, RMS value, average current, and phase difference step by step. ### Step 1: Combine the Sine and Cosine Terms We can express the current in a single trigonometric function using the following identity: ...
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