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: Marksman on a railroad car

  1. Oct 30, 2006 #1
    A marksman standing on a motionless railroad car fires a gun into the air at an angle of 30.0° from the horizontal (the figure below). The bullet has a speed of 175 m/s (relative to the ground) and a mass of 0.0110 kg. The man and car move to the left at a speed of 1.20 10−3 m/s after he shoots. What is the mass of the man and car?
    [Hint: A component of a system's momentum along an axis is conserved if the net external force acting on the system has no component along that axis.]

    fig026.gif

    I know that Pi = Pf where there is conservation of momentum.

    so M1V1i + M2V2i = M1V1f + M2V2f
    0 = M1V1f + M2V2f

    but I'm not sure what numbers to plug in because there is also an angle involved.
     
  2. jcsd
  3. Oct 30, 2006 #2
    Use the horizontal component of the bullet (it will involve a trig function [sin, cos, or tan] of the angle).
     
  4. Oct 30, 2006 #3
    thanks! i got the correct answer. :)
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook




Loading...
Similar Threads for Marksman railroad Date
A loaded railroad car is rolling at a constant velocity Mar 25, 2018
Man on a railroad car Feb 21, 2018
Man on a railroad car Jun 16, 2017
Projectile motion of marksman Jan 4, 2016
A firing marksman Oct 15, 2006