Practice portal › Alternating Current › Alternating Quantities: RMS and Mean
Asked in NEET 2026 · Instantaneous values and timing
Write the current as i=iₚₑₐₖ sin ω t with
ω=2π f=2π×60=120π rad s⁻¹.
It first reaches its peak when sin ω t=1, that is ω t=π/2.
t=π/(2×120π)=1/(240) s.
This is a quarter of the period T=1/(60) s, which is the general result: zero to peak
takes a quarter cycle.
Reading this solution needs no sign-in. You only sign in to practise against the clock and keep your progress.
Practise this with a timer