Answer: F = 25.1 kHz
Explanation:
Time (period) = 250 × 10^-6 s
Let's first calculate the folding frequency. Given by
NF (rad s-1) = π/Δt
where NF = Nyquist frequency
t = time increment between observations.
The original signal must be filtered by analog or physical methods to remove all frequencies higher than the Nyquist frequency before the signal is sampled or digitized.
F = 3.143/0.00025
F = 12566.37Hz
minimum sampling rate = 2F
2 × 12566.37 = 25132.74Hz
minimum sampling rate = 25.1 KHz