Results 1 to 5 of 5

Math Help - Another Physics problem

  1. #1
    Member
    Joined
    Aug 2012
    From
    new orleans
    Posts
    131
    Thanks
    1

    Another Physics problem

    A 1200 kg car traveling north at 10 m/s is rear-ended by a 2000 kg truck traveling at 31 m/s. What is the total momentum before and after the collision?

    before collision_______
    after collision___________





    Who said physics was easy online.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member
    Joined
    Sep 2012
    From
    Washington DC USA
    Posts
    525
    Thanks
    146

    Re: Another Physics problem

    Prior to the collision, can you find the magnitude of the momentum of the car?
    Of the truck?
    Now what about their directions, hence their momentum? (Remember that momentum is a vector!)
    So what was the total momentum (= momentum car plus momentum truck) prior to the collision? (Again, remember that momentum is a vector!)
    If you know the total momentum prior to the collision, what can you say about it after the collision?
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Member
    Joined
    Aug 2012
    From
    new orleans
    Posts
    131
    Thanks
    1

    Re: Another Physics problem

    put in number so I can read thx I'm super lost
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Forum Admin topsquark's Avatar
    Joined
    Jan 2006
    From
    Wellsville, NY
    Posts
    9,966
    Thanks
    350
    Awards
    1

    Re: Another Physics problem

    Quote Originally Posted by Louisana1 View Post
    put in number so I can read thx I'm super lost
    No numbers are needed. The net external force on the car and the truck system is 0 N. What can we say about the total momentum in this case? (Hint: The concept here is one that you will almost always use for problems dealing with total momentum.)

    -Dan
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Super Member
    Joined
    Sep 2012
    From
    Washington DC USA
    Posts
    525
    Thanks
    146

    Re: Another Physics problem

    I'll do a piece to get you started.
    The magnitude of the momentum of the truck is mass times velocity = (2000 kg)(31 m/s) = 62,000 kg m / s.
    The truck's direction of motion?
    Since the truck rear-ended the car, the truck was moving in the same direction as the car. Since the car was travelling north, so was the truck.
    Therefore the truck's momentum (a vector!) prior to the collision was 62,000 kg m / s due north.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. physics problem
    Posted in the Math Topics Forum
    Replies: 1
    Last Post: September 16th 2009, 04:58 PM
  2. Replies: 2
    Last Post: January 10th 2009, 05:49 AM
  3. Physics Problem
    Posted in the Math Topics Forum
    Replies: 3
    Last Post: November 19th 2007, 10:48 AM
  4. physics, acceleration, physics problem
    Posted in the Math Topics Forum
    Replies: 3
    Last Post: September 29th 2007, 03:50 AM
  5. Physics problem
    Posted in the Math Topics Forum
    Replies: 2
    Last Post: December 28th 2005, 11:23 PM

Search Tags


/mathhelpforum @mathhelpforum