top : rect pulse
bottom : it's fourier transform ( representing in frequency domain)

here shown are 3 rectangular pulses and their respective fourier transform
As the width of the rectangular pulse gets narrower, itÂ’s frequency domain expands laterally.
initutively, anyone knows why this happens?
also i heard it has something to do with the Lowest common multiple of the period of the main graph and it's harmonics
can some body please explain to me?
i read the book liao but they never explain in detail
expert please help
