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: Magnitude, Direction of Momentum, & Velocity

  1. Dec 7, 2008 #1
    1. The problem statement, all variables and given/known data

    A compact car, mass 775 kg, is moving at 1.00 multiplied by 10^2 km/h toward the east.

    (a) Find the magnitude and direction of its momentum.
    (b) A second car, mass 2125 kg, has the same momentum. What is its velocity? (in km/h)


    2. Relevant equations



    3. The attempt at a solution

    (a) 775 x 100 = 77,500 N s, to the east.. How do i convert this to kg m/s?

    (b) 77,500 = mass x velocity
    77,500 = 2125 x V
    velocity = 77,500 / 2125
    = 164,687,500 or 1.65 x 10^8 km/h
     
  2. jcsd
  3. Dec 7, 2008 #2

    rock.freak667

    User Avatar
    Homework Helper

    For the units you multiplied you'd get kg km/h

    to convert this to kgms-1

    you'd need to conert k (kilo) to 1000 and h (1 hour) to 360 seconds

    thus you'd need to multiply by 1000/360
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook