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!

A question of inherited velocity

  1. Apr 22, 2012 #1
    I'm playing a rather popular online fps type game that is extremely fast paced so your character is capable of moving at speeds in excess of 200kph.

    The question I have:

    Say I'm flying at 100kph in midair and i turn 90 degrees to my left and fire a shot.
    how much of my vector and velocity will be transferred to the projectile and how will it effect its trajectory?

    I know that its possible to cancel out the forces if you could fire the bullet directly 180 degrees off your vector and at the same speed <saw that episode of mythbusters>

    If anybody could point me at some refrence material so I can make a valid argument aginst their physics model that would be great

  2. jcsd
  3. Apr 23, 2012 #2


    User Avatar
    Science Advisor

    Velocities are vectors. You use vector addition to get the initial velocity of the bullet:


    a : your velocity relative to ground
    b : initial bullet velocity relative to you
    a+b : initial bullet velocity relative to ground

    You don't cancel out forces. But you can cancel out the bullets velocity component parallel to your flight path, so it goes 90° to your path in the ground frame. To do this you aim b backwards at an angle, so that a+b is perpendicular to a. Keep in mind that the length of b is multiple times that of a for a normal bullet and the speeds you mentioned.
  4. Apr 23, 2012 #3
    do you think the magnus effect will play any role in the trajectory of the shot? Assuming its a rifled bullet
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook