Q 12-07-049JEE MainJEE Main 2024 (4 Apr, Shift 1)Medium
An alternating current at any instant is given by $i = \left[6 + \sqrt{56}\sin(100\pi t + \pi/3)\right]\ \text{A}$. The rms value of the current is ______ A.
Numerical value type. Enter your answer.
Answer: 8
For a dc part $I_0$ plus a sinusoid of amplitude $A$: $I_{rms}^2 = I_0^2 + \dfrac{A^2}{2}$.
$$I_{rms} = \sqrt{36 + \frac{56}{2}} = \sqrt{64} = 8\ \text{A}$$
Solution by Sreeraj P, M.Sc Physics