# Find spectrum of a voltage wave

#### colbygatte

Joined Sep 5, 2011
6
I am lost.

Find the spectrum for a 0.1 second sample of a 50 Hz sinusoidal voltage wave.
All I can get out of this question so far that:

V=Asin(314t)

Do I use

$$S(f)=A\int^{.1}_{0}\sin{314t}e^{-j314t} dt$$

#### t_n_k

Joined Mar 6, 2009
5,455
Do I use

$$S(f)=A\int^{.1}_{0}\sin{314t}e^{-j314t} dt$$
No - you use

$$S(\omega)=A\int^{.1}_{0}sin(314t)e^{-j\omega t} dt$$

Perform the integration to determine the general relationship for S(ω) then plot S(ω) for an indicative range of values of the variable ω.