1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Momentum/exploding block

  1. Feb 1, 2007 #1
    1. The problem statement, all variables and given/known data

    A 2 kg block moves north at an unknown velocity. It then explodes into two blocks, the first one being 1.2 kg and moves EAST at 10 m/s, the second one is 0.8 kg and moves 22 m/s at an angle North of West.

    What is the initial MOMENTUM of the 2kg block?

    2. Relevant equations

    p initial = p final (momentum conserved)

    3. The attempt at a solution

    The answer i got was 13 kg m/s, and some friends of mine got 29.6 kg m/s. The reason i got 13 is because I think/thought the two horizontal components of the exploded blocks cancel out each other because they are in seperate directions (velocity is a vector and therefore one being negative one being positive, so I thought only the vertical component of the second block's momentum mattered).

    Any help is appreciated Thank You!
  2. jcsd
  3. Feb 1, 2007 #2

    Doc Al

    User Avatar

    Staff: Mentor

    You are correct; your friend is not. Good reasoning.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook