COMEDK · Physics · 23. Alternating Current
A group of devices having a total power rating of 500 watt is supplied by an AC voltage \(E = 200 \sin\left(3.14t + \frac{\pi}{4}\right)\). Assuming the current in the circuit is of the form \(I = I_0 \sin(3.14t)\), the r.m.s. value of the circuit current is
- A 500 A
- B 200 A
- C 1 A
- D 5 A
Answer & Solution
Correct Answer
(D) 5 A
Step-by-step Solution
Detailed explanation
\(E_0 = 200\) V, so \(E_{rms} = \dfrac{200}{\sqrt{2}}\) V Phase difference between voltage and current \(\phi = \dfrac{\pi}{4}\) Power factor \(= \cos\dfrac{\pi}{4} = \dfrac{1}{\sqrt{2}}\) \(P = E_{rms} \cdot I_{rms} \cdot \cos\phi\)…
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