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Homework Help: Ppl i am just 14 and am tryin to make a car and i am having problems

  1. Nov 14, 2009 #1
    ppl i am jus 14 and tryin to make a car
    the amount of phsics i no is a bit less
    i started calculating
    by assuming:-
    car weight = 50kg
    passenger weight 50 kg
    propultion system weight =5okg
    total weight =150 kg
    speed 20km/h = 5.5m/s
    i am taking =5 m/s approx
    time taken= 10 sec
    acceleration =0.5m/s2
    force =150 x 0.5=75 newton
    energy =1875juoles = 1.875kj
    power = 187.5 watt
    my question is that **"how much slope can it move on??"**
    coz i dont no cos tan sin
    Last edited: Nov 14, 2009
  2. jcsd
  3. Nov 14, 2009 #2
    Re: physics query i am tryin 2 make a car ppl, plz reply

    ppl reply i need ur help
  4. Nov 14, 2009 #3
    Formatting and full comprehensive sentences are your friend.

    You need to know the thrust at the wheels.

    Found from engine torque * gear ratio * rolling radius.
    This will give you the max force available at the wheels.

    F = mg sin theta

    Run for a range of theta, and you can find the max slope you can get up.
    or rearrange or theta and work it out with arcsin (I dont know if you will have learnt that at 14)
    Last edited: Nov 14, 2009
  5. Nov 17, 2009 #4
    hey can u find it for me i am havin problem
  6. Nov 17, 2009 #5
    I can't find it for you, I have told you how to find it though.
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