<p>Don’t forget to take into account that the moment of inertia will not be the same. Use conservation of momentum ot figure out the relationship between the radii. You can use conservation of momentum because it says NO EXTERNAL FORCES are applied, meaning momentum is conserved.</p>
<p>A uniform spherical planet has radius R and acceleration due to gravity at its surface g. What is the escape velocity of a particle from the surface? </p>
<p>Answer is √2gR, but the escape velocity depends on the mass of the planet and the gravitational constant, doesn’t it?? I calculated v = √(2GM / R) </p>
<p>If you set F = GMm/R^2 according to newtons law of universal gravitation, you can substitute GM/R^2 as g, making F=mg, the more familiar looking form. In your radical you have √(2GM/R), and you can substitute GM/R as gR. I’m taking the test in a few hours, wish me luck!</p>
<p>LUCK! I WISH YOU LUCK! PLENTY OF LUCK! And thanks. </p>
<p>Well? Eh? Eh? Eh? </p>
<p>How was it?</p>
<p>I AM DONE!!!</p>
<p>SirEdge add me on gmail.</p>
<p>I smell triumph. Well done Radbg. </p>
<p>LOL it is not referring to how I felt about the test. I’m just glad this is out of the way. Time to relax until results come out.</p>
<p>if you took the test already, pm me!</p>
<p>I hope you’re all willing to talk about the test with me later this week. Don’t leave me out. I’m taking it Thursday. </p>
<p>Guys! I took the test today! Its pretty tricky!</p>
<p>How was the test?</p>
<p>jzhang, let’s not talk about it with the people who haven’t taken it or hint at the test. </p>
<p>I have a friend who took it today. We’re frenemies/ competitors, and she won’t tell me anything (not that I’d stoop low enough to ask). She had to take it early because of a conflict. She doesn’t care about it, just took it for the fun of it. </p>
<p>I’m worried because another girl who is taking the test is one of her best friends…</p>
<p>Alright everyone, let’s just not talk about it until the testing period is over. I’m getting quite a few pm’s which are obviously from people who are trying to cheat (not going to name names, but let’s say at least one has posted on this thread). Let me just say one thing to you guys.</p>
<p>You’re embarrassing yourselves, the people who are supporting you, and the institution that you represent, or will represent.</p>
<p>Thanks. Now that we’ve got that out of the way, please continue. :)</p>
<p>Okay, but could you guys tell me this? </p>
<p>How well did you do on past practice exams? Like, how many of the problems could you solve (no time limit)?</p>
<p>And with that in mind, how confident are you that you got to the next round in this exam? </p>
<p>Well, for the people who have taken it, what do you estimate the cutoff to be relative to previous years?</p>
<p>Honestly this test was a lot harder than all the others, and even av extended time limit wouldn’t have helped me much 
2013 wasn’t too difficult without time pressure, but this is a new story
Pretty sure cutoff will be around 11 or so if last year was 12.5</p>
<p>holy crap seriously? does anyone second siredge’s opinion? </p>
<p>@siredge, have you taken the 2013 exam? </p>