this post was submitted on 15 Jan 2025
282 points (98.0% liked)

xkcd

9475 readers
15 users here now

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

founded 2 years ago
MODERATORS
 

Edit: Alt Text: Speed limit c arcminutes^2 per steradian.

you are viewing a single comment's thread
view the rest of the comments
[–] addie@feddit.uk 46 points 1 month ago (24 children)

For something that doesn't run continuously, like eg. a refrigerator, then an average daily usage is more useful, no? "This product draws 1.5 kW with a duty cycle of 0.08" doesn't really help when comparing efficiencies of potential purchases, you'd need to convert it to electricity consumed in a set period anyway.

[–] kittehx@lemmy.blahaj.zone 20 points 1 month ago (3 children)

No, it's because watts are joules per second, so kWh are (energy / time) * time. Cancelling the units would be expressing the energy directly in joules.

[–] RvTV95XBeo@sh.itjust.works 12 points 1 month ago (2 children)

But the XKCD mentions kWh/day specifically, in theory the times can cancel out, leaving you with kW

But instantaneous and average kW are very different, and it would take more time to describe that distinction than to use kWh/day.

[–] kittehx@lemmy.blahaj.zone 2 points 1 month ago

Ok that's fair, I kinda glossed over that part. Both are valid interpretations, I think.

load more comments (1 replies)
load more comments (1 replies)
load more comments (21 replies)