## Search found 7 matches

Mon Jun 09, 2014 3:53 pm UTC
Topic: 1379: "4.5 Degrees"
Replies: 879
Views: 155307

### Re: 1379: "4.5 Degrees"

mel_env_eng: I'm curious about Randall's source for [200m sea level rise]. For the record, the 80m sea level rise which I mentioned is from http://pubs.usgs.gov/fs/fs2-00/ , where this is given as the result of complete melting of Greenland and Antarctic ice sheets. I've seen other estimates closer ...
Mon Jun 09, 2014 1:07 pm UTC
Topic: 1379: "4.5 Degrees"
Replies: 879
Views: 155307

### Re: 1379: "4.5 Degrees"

As with some others here, I was disappointed in the accuracy here. There have been a couple of earlier ones on this topic (climate change) with which I disagreed, but this one went way too far in my estimation. I am heartened to see that others had a similar reaction. In particular, I like synp's co...
Tue Jun 29, 2010 4:20 am UTC
Topic: 0759: "3x9"
Replies: 135
Views: 42612

### Re: "3x9" Discussion (#759)

Here's my favorite "accidentally correct math" problem. Suppose you have a b c a where a, b and c are single-digit numbers, and on the next line you make the mistake of writing down the 4-digit number abca instead. What values of a, b and c actually make this work -- that is, a b c a = abc...
Wed Dec 30, 2009 11:36 pm UTC
Topic: 0681: "Gravity Wells"
Replies: 205
Views: 57242

### Re: "Gravity Wells" Discussion

Re-looking at my previous post, I'm not sure what's going on with the satellites. The energy to reach low earth orbit (and corresponding well depth) would have to be a lot higher (about half of the escape height) I think you're including the kinetic energy of the satellite, but per the alt-text (we...
Wed Dec 30, 2009 4:13 am UTC
Topic: 0681: "Gravity Wells"
Replies: 205
Views: 57242

### Re: "Gravity Wells" Discussion

WooperSlim wrote: Here's what I don't get. My "layman's terms" interpretation would be: if you throw something at escape velocity, but then gravity never diminished the farther away from the body, what would the maximum height be? The reasoning being that if you were to throw something tha...
Wed Dec 30, 2009 3:09 am UTC
Topic: 0681: "Gravity Wells"
Replies: 205
Views: 57242

### Re: "Gravity Wells" Discussion

Along the same lines, I want to pick a nit. In the Earth inset, the dotted line apparently is the reference point of zero potential energy relative to the Earth's gravity. Randall's simplifying methodology gives the well-depth from that line to as (R earth )^2 / r, where r is the distance of the obj...
Mon Sep 29, 2008 5:53 am UTC