whim vs impulse

whim and impulse both are nouns.

Word	Noun	Adjective	Verb	Adverb
whim	Yes	No	No	No
impulse	Yes	No	No	No

As nouns, whim and impulse are synonyms defined as:

Other synonyms of whim include caprice.

whim (noun)	impulse (noun)
an odd or fanciful or capricious idea	the act of applying force suddenly
a sudden desire	an impelling force or strength
	the electrical discharge that travels along a nerve fiber
	(electronics) a sharp transient wave in the normal electrical state (or a series of such transients)
	a sudden desire
	an instinctive motive