247
xkcd #3289: Highway Signs (imgs.xkcd.com)
submitted 2 months ago by [B] to c/xkcd@lemmy.world
9 comments fedilink hide all child comments
 

xkcd #3289: Highway Signs

Title text:

Highway engineers like Planck units because, like the speed of light, the energy capacity of a typical car's gas tank is 1.

Transcript:

Transcript will show once it’s been added to explainxkcd.com

Source: https://xkcd.com/3289/

explainxkcd for #3289

Highway engineers like Planck units because, like the speed of light, the energy capacity of a typical car's gas tank is 1.

all 9 comments

sorted by: hot top controversial new old
[–] 28 points 2 months ago (4 children)

Scientific notation is great and all but sometimes you just need a bunch of zeroes in the number to really hammer in how big/small something is.

  • permalink
  • fedilink
  • source
  • hideshow 4 child comments
    •
  • [–] 3 points 2 months ago (3 children)

    I like doing a little magic trick when I have to guesstimate base 10 logarithm of a number by looking at its length. It feels like I'm doing something wrong and yet it works.

  • permalink
  • fedilink
  • source
  • parent
  • hideshow 3 child comments
    •
  • [–] 4 points 2 months ago (2 children)

    This one should be roughly 39.1. It has 39 digits after the 1, 1.39 cubed is closer to 2 than 4, and 2 has a natural logarithm 0.3 so 1.39 should have a natural logarithm of roughly 0.1.

    idk why would it feel wrong tho? when the logarithm is greater than zero, the integer part of it is how long it is minus one.

  • permalink
  • fedilink
  • source
  • parent
  • hideshow 2 child comments
    •
    • [–] 10 points 2 months ago

    Still saner than imperial

  • permalink
  • fedilink
  • source
    •
    [–] 3 points 2 months ago (1 child)

    http://www.rogermwilcox.com/Planck_ruler.html

    I can't believe I get to share this old website and have it be relevant for once!

  • permalink
  • fedilink
  • source
  • hideshow 1 child comment
    •
    • [–] 2 points 2 months ago

    Love also CGS system for electrical related stuff...

    Battery rated for 0.3836g^1/2^c^1/2^s^−1^, capacity 3,236,000,000,000g^1/2^c^3/2^s^−1^

  • permalink
  • fedilink
  • source
    •