Difference between revisions of "Talk:135: Substitute"

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Your wrong, I've bought a shit load of Fords over the last 15 years and they're are ineded the cheapest and most available, but you get what you pay for with Ford and thats cheap shit, I don't know what ratings your looking at but in the 90s-2004 Ford trucks were rated some of the worst vehicles to buy depending on reliability, while Dodge and GM had some of the best ratings, Now after 2004 Fords ratings are getting better but no where near the quality of GM and Dodge. I own all three.
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[[User:Rikthoff|Rikthoff]] ([[User talk:Rikthoff|talk]]) The issue date is off, as i can't find a create date for the image. Can anyone fix?
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:Yes, I've fixed the date on the page. [[User:Lcarsos|lcarsos]] ([[User talk:Lcarsos|talk]]) 15:30, 14 September 2012 (UTC)
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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. 
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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. [[User:Blaisepascal|Blaisepascal]] ([[User talk:Blaisepascal|talk]]) 22:18, 14 September 2012 (UTC)

Revision as of 12:35, 8 January 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)

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