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Education Physics Problems!

Discussion in 'General' started by Bogomip, 5 Oct 2011.

  1. thehippoz

    thehippoz What's a Dremel?

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    oh I see what your saying.. yeah that's true, the horseman does 225m total

    he's traveled 150m forward with the brigade when he hit the front.. but on the way back.. he's running the 100m and the brigade has moved 25m in thew opposite direction.. so he runs 75m on the way back
     
  2. mvagusta

    mvagusta Did a skid that went for two weeks.

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    That would be true if the question said he was travelling at double the speed.
    But it says he's going 3x the speed! Triforce!!!111

    edit: you ninja'ed me.

    The officer only covers 200m total, due to the cancelling out of extra distances, so 225m is incorrect.
     
  3. thehippoz

    thehippoz What's a Dremel?

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    no you were right.. at any speed he will travel 225m
     
  4. thehippoz

    thehippoz What's a Dremel?

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    well easier if make a diagram.. I dunno why but it bugs me you don't see it :p

    I put the speedometer on the brigade.. think of it in 2d might be easier- the horse will be running 30 mps in this instance but against the brigade, 20 (30-10)


    [​IMG]
     
  5. mvagusta

    mvagusta Did a skid that went for two weeks.

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    Yes if the troupe travels 75m, then the officer travels 225m... my point was that 225m is proof that 75m is the incorrect answer to the question!

    I'm on the phone atm, so it would be a pita to draw and post a diagram.... I wonder if any conclusions from the rest of bit tech's mathematicians have now changed?
     
  6. thehippoz

    thehippoz What's a Dremel?

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    yeah sorry drew that up quick.. was watching survivor xD

    now look at it, it's not so clear in that diagram.. the speedometer and the horse are connected.. it's the speed of the horse against the brigade.. maybe that might help you see it better

    the 225 for the horse travel is correct.. 150 forward, 75 back
     
  7. thehippoz

    thehippoz What's a Dremel?

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    you can plug in any numbers.. let's say the speed of the brigade is 22mps and the horse runs 4x the speed of the brigade

    so the horse now runs 88mps

    now against the brigade he's running 66mps (because the brigade is moving forward at 22mps.. 88-22)

    now let's get the percentage 22/66=33.3333333% and that works with any speed if you do the math above..

    on the way back the horse is running 4 times 22mps or any speed really, but the brigade is still moving forward at 22 in this example.. so 22 multiplied by 4 we get 88 again.. now add 22mps to 88 because of the brigades forward speed.. and we get 110mps for the horse

    so against the brigade, the horse is now running 110mps towards the back.. now let's get the percentage to figure out the back run.. 22/110=20%

    so now let's add up both percentages 33.3333% and 20% = 53.3333%

    multiply that by the length of the brigade for the answer on how far the brigade has traveled
     
  8. Bungletron

    Bungletron Minimodder

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    Wrong again teacherman! :lol: In fact it was Xir who pipped me, what the question Xir?
     
  9. Byron C

    Byron C Multimodder

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    So instead of a "suggest some physics problems I can use in class" thread, this is now a "here's some physics problems for you to solve/debate" thread ;).
     
  10. thehippoz

    thehippoz What's a Dremel?

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    trying to help mv.. he was going to lose his 460 over some physics problem any elementary student in gate could solve

    I used to be stubborn like that too.. that's what cool about math- actually like journeys answer it's a lot more simple- but trying to explain it in a deeper way is always hard to do.. why I'm not a teacher :hehe: (my girl is though)
     
  11. Bogomip

    Bogomip ... Yo Momma

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    Pff, I worked out the answer properly within about 3 mins of getting it.

    I however used maths, as opposed to heresay, conjecture and opinion :) The guy who got it in this thread did it a much simpler way than me too, which im a bit miffed about. The graph is a thing of beauty! :)
     
  12. Krikkit

    Krikkit All glory to the hypnotoad! Super Moderator

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    It is quite lovely. I just scribbled a bit of crap out on paper between jobs at work and got it epically wrong. :D
     
  13. mvagusta

    mvagusta Did a skid that went for two weeks.

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    lmao :hehe: that's funny :lol:

    Lets up the stakes, incorrect answer buys the other player a complete high end pc, including ssd's, big ips monitors, gtx 590, i7, whatever you like :D

    Wanna play?
     
  14. thehippoz

    thehippoz What's a Dremel?

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    aye I already explained it best I could.. make a bet with bungle- I'm sure he'd be happy to take a rig off your hands

    don't do it mv! =-] I could try to explain it another way but I'm busy tonight.. my moms coming over from alaska to visit

    maybe one of these other guys would explain it a bit better too :hehe: :worried:
     
  15. mvagusta

    mvagusta Did a skid that went for two weeks.

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    Too late now, I've invested more than a moment's thought to the problem, and made a quick scribble on a bit of paper, and I now have irrefutable proof that the troupe cover 75m by the time that fcuking annoying officer completes his Mel Gibson impersonation :D

    This could have been bit-tech's super month of give aways :lol: Pfft @ppl that can't give away crt's, I can't even give away new hardware!
     
  16. Xir

    Xir Modder

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    I was hoping the thread starter had the correct answer in the first place :D

    My first approach was drawing it too (though I did in in excel)
    The second approach was using relativistic speed
    Both give out 75m of troup-travel independent of used speed.

    There's a third way of solving this, by calculating both crosspoints using derivative maths...
    This would be the sure way, but I can't be arsed to read up on that right now.
     
  17. Xir

    Xir Modder

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    Hellair?
     

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