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Homework Help: Doubts regarding 3 question form motion of a particle!

  1. Dec 4, 2012 #1
    Doubts regarding 3 question form motion of a particle! :)

    1. The problem statement, all variables and given/known data

    Doubts related to 3 problems..I have uploaded the question up in the attachment.

    2. Relevant equations



    3. The attempt at a solution
    for question one,the body doesnt come to rest,s is the total dist at any instant after it started decelerating with retardation β.If it comes to rest,answer is 2s/v,and such a problem is there in irodovs general problems book..but how to get a general equation,for any instant after it starts decelrating with b?

    question 3:i attempted using vectors and taking dot product equal to zero,but didnt arrive anywher,so someone please help! :)
     

    Attached Files:

  2. jcsd
  3. Dec 4, 2012 #2
    Re: Doubts regarding 3 question form motion of a particle! :)

    Someone please Reply!! :(
     
  4. Dec 4, 2012 #3

    SammyS

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    Re: Doubts regarding 3 question form motion of a particle! :)

    Hello zacky_D. Welcome to PF !
    Patience, Please !

    While you're waiting for a reply, please read the rules for this Forum. You will see there that you should wait 24 hours before "bumping" your thread.


    For Problem #1: You are correct in regards to you conclusion that the car nedds to come to rest in order for a solution to be possible.

    As regards the somewhat similar Irodov problem, I believe that the Irodov problem assumes that the magnitude of the acceleration, α, is equal to the magnitude of the deceleration, β. In that case, the total time is s/vaverage = 2s/vmax. You generally would want to express this answer in terms of s and α, not s and vmax .


    As for your attempt at a solution to #3: You will need to give more details as to what you tried, before we can be of much help.
     
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