whining sound

hi i have a 1998 t/c with 88000 miles on it yesterday if i rev it in park i get a whining sound from under the hood. and if i'm driving i hear it seems to go with the rev of the motor.i tried to listen it seems to be at the top of the motor could
it be the alternator or what else could it be.the noise isn't contant only when
the motor revs

If the noise is a high pitched noise and you hear static on the radio, then it could be the alternator.
If it is a whine that sounds like a high pitched tired moaning sound, then the power steering pump is going bad.
If it is a throbbing rumbling rattle sound, then the water pump is going bad.
Also check the belt tensioner.