A rock in the sun
Conversation
Haystack
1
5
Spiky conker things
1
5
Assorted gorse bushes
1
4
Dry rocks on a beach
2
4
Wet rocks on a beach
3
5
Reminds me of lots of beaches in Nova Scotia where I grew up ♥️
Huge tides so we'd see a lot of wet rocks!
Quote Tweet
Replying to @WeftOfSoul
Meanwhile I grew up a literal stone's throw from the bay with the highest tides in the world, so when I go anywhere with ordinary 2-4m tides it basically feels like there's no tides.
Image below is not my hometown but I had to look for a couple seconds to be certain.
1
2
Tides is something I've been meaning to look into
How can the moon be so far away and be pulling such a huge amount of water this way and that?
Something doesn't add up
2
2
here’s another thing that confuses me: in most places the tides are roughly in a 12-hour cycle, meaning 2 high tides and 2 low tides a day (“semi-diurnal”). the naive analysis using the fact that the moon orbits about once a day would suggest that it ought to be about 24 hours
1
3
We've been doing some more digging but it's still not that clear
Quote Tweet
That doesn't, intuitively, to me, explain why high tide is twice a day though, moon-side and far-side. Something I've been looking at in this quest today said something about inertia for that though. Hmm…
Show this thread
1
2
i came across a pdf that claims the key is to account for the centrifugal force of the earth’s rotation but i still don’t grok it and now i’m super confused about wtf an inertial reference frame even is
whoi.edu/cms/files/lect
Replying to
Incidentally, I watched this video a week ago and now I think I understand inertial reference frames better.
Centrifugal forces appear when you have a rotating frame of reference (around 8mins in the video).
(featuring Terry Tao & MathOverflow)
youtube.com/watch?v=1VPfZ_
2
1
but rotating with respect to *what*? the earth is just hanging out in space! what is it rotating with respect to!!!
2
Show replies