this post was submitted on 25 Jun 2025
441 points (97.8% liked)

xkcd

11711 readers
551 users here now

A community for a webcomic of romance, sarcasm, math, and language.

founded 2 years ago
MODERATORS
441
xkcd #3106: Farads (imgs.xkcd.com)
submitted 1 day ago* (last edited 1 day ago) by [email protected] to c/[email protected]
 

xkcd #3106: Farads

Title text:

'This HAZMAT container contains radioactive material with activity of one becquerel.' 'So, like, a single banana slice?'

Transcript:

[Cueball holds a stick while talking with Megan and White Hat.]
Cueball: This stick is one meter long.
Megan: Cool.
White Hat: That's a nice stick.

[Cueball holds a smallish rock.]
Cueball: This rock weighs one pound.
Megan: I'd believe it.
White Hat: Looks like a normal rock.

[Cueball holds a small battery.]
Cueball: This battery is one volt.
Megan: Seems fine.
White Hat: Might need a recharge.

[Cueball holds a capacitor while Megan and White Hat panic.]
Cueball: This capacitor is one farad.
Megan: Aaaaa! Be careful!!
White Hat: Put it down!!

Source: https://xkcd.com/3106/

explainxkcd for #3106

you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 13 points 1 day ago (7 children)

A capacitor of 1 farad at standard American 120 volts has the energy between 7.62×54 and .50 BMG, and will discharge just as violently.

[–] [email protected] 16 points 1 day ago* (last edited 1 day ago) (5 children)

Great. Now I get to be the "I’m not familiar with that unit of measurement." guy.

7.62x54

3,291 J (2,427 ft⋅lbf) to 3,400 J (2,508 ft⋅lbf)

.50 BMG

The .50 BMG round can produce between 10,000 and 15,000 foot-pounds force (14,000 and 20,000 J), depending on its powder and bullet type, as well as the weapon it is fired from

[–] [email protected] 16 points 1 day ago (4 children)

foot-pounds

Oh, you Americans and your silly made-up units.

[–] [email protected] 2 points 1 day ago

Didn't even need to translate to foot-pounds-force, since .50 BMG was already in freedom-loving units.

load more comments (3 replies)
load more comments (3 replies)
load more comments (4 replies)