Difference between revisions of "Talk:135: Substitute"

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I don't think there is enough information to solve the second problem, because you don't know how fast the non-injured raptors go. Unless you take that information from the first problem. But then, how fast does the wounded raptor accelerate? You would have to find the angle where the wounded and the closest non-wounded raptor would meet you at the same time. [[Special:Contributions/213.127.132.140|213.127.132.140]] 17:17, 5 September 2013 (UTC)
 
I don't think there is enough information to solve the second problem, because you don't know how fast the non-injured raptors go. Unless you take that information from the first problem. But then, how fast does the wounded raptor accelerate? You would have to find the angle where the wounded and the closest non-wounded raptor would meet you at the same time. [[Special:Contributions/213.127.132.140|213.127.132.140]] 17:17, 5 September 2013 (UTC)
  
With all three raptors and me running at top speeds, I believe that you must run directly towards the wounded raptor and the two non-injuried raptors will reach you before you and the injured raptor meet, and you cannot do better.  After all, you can try to run from an uninjured raptor, but you will lose ground at a rate of at least 25-6=19 m/s.  By running at the injured raptor, you lose ground from it at the rate of 10+6=16 m/s.--DrMath 04:01, 24 October 2013 (UTC)
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I don't think you get caught by the injured raptor and uninjured raptor at the same time.  With all three raptors and you running at top speeds, I believe that you must run directly towards the wounded raptor and the two non-injuried raptors will reach you before you and the injured raptor meet, and you cannot do better.  After all, you can try to run from an uninjured raptor, but you will lose ground at a rate of at least 25-6=19 m/s.  By running at the injured raptor, you lose ground from it at the rate of 10+6=16 m/s.--DrMath 04:01, 24 October 2013 (UTC)
  
 
For 1 and 2 the solution depends on whether the raptors can accelerate at 2m/s, or they actually increase their speed at this rate. If they just accelerate, It should be possible to do tight circles, and even wind yourself slowly towards another location. I believe this is possible even treating yourself and the raptors as point masses. [[Special:Contributions/2.102.215.18|2.102.215.18]] 13:19, 17 July 2013 (UTC)
 
For 1 and 2 the solution depends on whether the raptors can accelerate at 2m/s, or they actually increase their speed at this rate. If they just accelerate, It should be possible to do tight circles, and even wind yourself slowly towards another location. I believe this is possible even treating yourself and the raptors as point masses. [[Special:Contributions/2.102.215.18|2.102.215.18]] 13:19, 17 July 2013 (UTC)
  
 
This could also be a parody of Snape substituting for Lupin (Harry Potter and the Prisoner of Azkaban) in the Defense against Dark Arts class. Snape assigns homework on werewolves, in the hopes of one of the students connecting the dots. Here, Randall might be trying to get the students to suspect that Mrs.Lenhart might be a raptor (out of sympathy, or just being a classhole?). Also [[155]]. [[Special:Contributions/208.124.118.63|208.124.118.63]] 18:58, 1 October 2013 (UTC)BK201
 
This could also be a parody of Snape substituting for Lupin (Harry Potter and the Prisoner of Azkaban) in the Defense against Dark Arts class. Snape assigns homework on werewolves, in the hopes of one of the students connecting the dots. Here, Randall might be trying to get the students to suspect that Mrs.Lenhart might be a raptor (out of sympathy, or just being a classhole?). Also [[155]]. [[Special:Contributions/208.124.118.63|208.124.118.63]] 18:58, 1 October 2013 (UTC)BK201

Revision as of 04:04, 24 October 2013

Rikthoff (talk) The issue date is off, as i can't find a create date for the image. Can anyone fix?

Yes, I've fixed the date on the page. lcarsos (talk) 15:30, 14 September 2012 (UTC)

1. It takes the raptor 25m/s / 4m/s^2 = 6.25s to reach it's top speed, during which I can run 6.25s * 6m/s = 37.5m. Add on my 40m head start, and I can reach a spot 77.5m away from the raptor before he gets me. In the same time, the raptor can run 4m/s^2 * (6.25s)^2 / 2 = 78.125m. I'm eaten before he's fully up to speed. Therefore, I have to solve for when the raptors location, r(t) = 4m/s^2 * t^2 /2 - 40, and my location, m(t) = 6m/s*t, are equal. Dropping units, we get 2t^2 -40 = 6t, or 2t^2 - 6t - 40 = 0. Dividing by 2 I get t^2 - 3t - 20=0. Using the quadratic equation, I get (3 +/- sqrt(89))/2, roughly equal to 6.217s and -3.217s. Plugging that back into m(t), I get 37.302m for my terminal run. Blaisepascal (talk) 22:18, 14 September 2012 (UTC)

I don't think there is enough information to solve the second problem, because you don't know how fast the non-injured raptors go. Unless you take that information from the first problem. But then, how fast does the wounded raptor accelerate? You would have to find the angle where the wounded and the closest non-wounded raptor would meet you at the same time. 213.127.132.140 17:17, 5 September 2013 (UTC)

I don't think you get caught by the injured raptor and uninjured raptor at the same time. With all three raptors and you running at top speeds, I believe that you must run directly towards the wounded raptor and the two non-injuried raptors will reach you before you and the injured raptor meet, and you cannot do better. After all, you can try to run from an uninjured raptor, but you will lose ground at a rate of at least 25-6=19 m/s. By running at the injured raptor, you lose ground from it at the rate of 10+6=16 m/s.--DrMath 04:01, 24 October 2013 (UTC)

For 1 and 2 the solution depends on whether the raptors can accelerate at 2m/s, or they actually increase their speed at this rate. If they just accelerate, It should be possible to do tight circles, and even wind yourself slowly towards another location. I believe this is possible even treating yourself and the raptors as point masses. 2.102.215.18 13:19, 17 July 2013 (UTC)

This could also be a parody of Snape substituting for Lupin (Harry Potter and the Prisoner of Azkaban) in the Defense against Dark Arts class. Snape assigns homework on werewolves, in the hopes of one of the students connecting the dots. Here, Randall might be trying to get the students to suspect that Mrs.Lenhart might be a raptor (out of sympathy, or just being a classhole?). Also 155. 208.124.118.63 18:58, 1 October 2013 (UTC)BK201