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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


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    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
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