Question

The equation of an alternating current is $i = 50\sqrt{2} \times \sin 400\pi t$ ampere then the frequency and the root mean square of the current are respectively

• A. 200 Hz, 50 amp
• B. 400 π Hz, $50\sqrt{2}$ amp
• C. 200 Hz, $50\sqrt{2}$amp
• D. 50 Hz, 200 amp

Answer 1

Answer: (A)

200 Hz, 50 amp

Answer 2

Comparing the given equation with $i = i_{0}\sin\omega t$

⇒ ω = 400 π ⇒ 2πν = 400π ⇒ ν = 200 Hz.

Also $i_{rms} = \frac{i_{0}}{\sqrt{2}} = \frac{50\sqrt{2}}{2}$= 50 A.