the third prong (ground prong) on my amp's power cord broke off, is it safe to use it with the missing prong?
DON'T!!! get it taken to an electrician/tech ASAP and fix it! or suffer a painful death...your choice
My MAIN Gear
"They call him the 'Sand Spider.' -Why? -Probably because it sounds scary"
*Agile AL3000 Les Paul w/ Alnico IIs
*Randall RM50
*Dunlop CFH
*fellow LEO feel free to give a shout out
You can get the replacement piece for $3-5 and replace it easily. Then you have a more solid plug than before too. There is no charge in it when it's unplugged anyway, I actually had this same situation and just clipped the end off and installed the new one in 2 minutes.
Quote by Jearl

...dont play Fender just because its Fender.

Ibanez SZ520QM
Peavey Rotor EXP
Squier Bullet (heavily modified)
Mesa Roadster Head & 2x12 cab