Results 1 to 3 of 3

Math Help - [SOLVED] mechanics

  1. #1
    Newbie
    Joined
    Aug 2008
    Posts
    4

    [SOLVED] mechanics

    Can anyone help please?

    A particle P starts from rest from a point A and moves alonga straight line with a constant acceleration of 2ms
    at the same time, a second particle Q is 5m behind A and is moving in the same direction as P with a speed 5ms
    if Q has a constant acceleration of 3ms find how far from A it overtakes P
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Junior Member
    Joined
    Aug 2008
    From
    Chicago, IL
    Posts
    73
    Quote Originally Posted by divine_mail View Post
    Can anyone help please?

    A particle P starts from rest from a point A and moves alonga straight line with a constant acceleration of 2ms
    at the same time, a second particle Q is 5m behind A and is moving in the same direction as P with a speed 5ms
    if Q has a constant acceleration of 3ms find how far from A it overtakes P
    start by making a table
    t p q
    0 0 -5
    1 2 2
    2 6 12
    3 12 25

    this gives you an idea of whats happening. you can see that you can make an equation for both particles

    we know that acceleration for p, or p'' is:
    p''=2 so we can get
    p' = 2x + c where c represents initial speed, in this case...
    p' = 2x + 0 (it started at rest)
    then we find its position
    p = x^2 + c where c=0 (or at least 5 more than c in q(x))

    then do the same for q
    q''= 3
    q' = 3x + c (initial speed was 5m/s)
    q' = 3x + 5
    q = (3/2)x^2 + 5x + c (initial positon was 5 behind p)
    q = (3/2)x^2 + 5x - 5

    now set p and q equal to eachother and that will tell you the moment they intersected.
    Last edited by Dubulus; August 8th 2008 at 12:19 PM. Reason: messed up the table
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Forum Admin topsquark's Avatar
    Joined
    Jan 2006
    From
    Wellsville, NY
    Posts
    10,211
    Thanks
    419
    Awards
    1
    Quote Originally Posted by divine_mail View Post
    Can anyone help please?

    A particle P starts from rest from a point A and moves alonga straight line with a constant acceleration of 2ms
    at the same time, a second particle Q is 5m behind A and is moving in the same direction as P with a speed 5ms
    if Q has a constant acceleration of 3ms find how far from A it overtakes P
    And please note that the acceleration is given in units of m/s^2, not ms.

    -Dan
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. [SOLVED] Electrostatics and Mechanics?
    Posted in the Advanced Applied Math Forum
    Replies: 5
    Last Post: June 15th 2009, 04:16 PM
  2. [SOLVED] Mechanics - Collisions?
    Posted in the Advanced Applied Math Forum
    Replies: 1
    Last Post: May 17th 2009, 10:44 PM
  3. [SOLVED] Mechanics problem?
    Posted in the Advanced Applied Math Forum
    Replies: 6
    Last Post: April 23rd 2009, 07:27 AM
  4. [SOLVED] Mechanics question
    Posted in the Advanced Applied Math Forum
    Replies: 4
    Last Post: February 26th 2009, 09:13 AM
  5. [SOLVED] Mechanics problem
    Posted in the Advanced Applied Math Forum
    Replies: 2
    Last Post: February 25th 2009, 10:19 AM

Search Tags


/mathhelpforum @mathhelpforum