xkcd

11725 readers

292 users here now

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

founded 2 years ago

MODERATORS

[email protected]

454

xkcd #3106: Farads (imgs.xkcd.com)

submitted 3 days ago* (last edited 3 days ago) by [email protected] to c/[email protected]

89 comments fedilink hide all child comments

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] 14 points 3 days ago (2 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] 2 points 2 days ago (1 children)

So what you're saying is that if I touched that in the wrong manner I'd get blown across the room?

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

Uh yeah, I'm pretty sure the discharge can stop your heart if you grab it in precisely wrong manner. Typical defibrillator uses like 50 times less energy, but with a higher voltage.

[–] [email protected] 18 points 3 days ago* (last edited 3 days ago) (1 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] 18 points 3 days ago (3 children)

foot-pounds

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

[–] [email protected] -2 points 2 days ago

Oh you non-Americans and your lack of wheelchair access ramps.

See how stupid and annoying this is?

[–] [email protected] 2 points 3 days ago

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

[–] [email protected] 10 points 3 days ago (1 children)

All units are made up.

I totally agree that imperial units are silly, though. Base 10 is the way things should be.

[–] [email protected] 3 points 2 days ago* (last edited 2 days ago)

But then we'd miss the fun of domain specific units, like A barn