The Big Bang Theory Season 5, Episode 7

(electrical crackling, popping)

The Big Bang Theory Season 3, Episode 2

Actually, ethyl alcohol inhibits electrical conduction in the nerve cells...

The Big Bang Theory Season 11, Episode 8

Tesla was a genius who invented our electrical grid.

The Big Bang Theory Season 5, Episode 16

And an electrical charge.

The Big Bang Theory Season 2, Episode 12

Yeah, no. A little electrical tape, some solder...