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Homework Help: Relitive Motion

  1. Sep 24, 2008 #1
    While driving North at 25 m/s during a rainstorm you notice that the rain makes an angle of 38 degrees with the vertical. while driving back home moments later at the same speed but in the opposite direction, you see that the rain is falling straight down. From these observations, determine the speed and angel of the raindrops relative to the ground.

    i have no clue how to even start this
  2. jcsd
  3. Sep 25, 2008 #2


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    Welcome to PF!

    Hi laxman31757! Welcome to PF! :smile:

    This is a vector addition problem …

    velocities are vectors, so you can combine them using a vector triangle …

    write Vcg for the velocity of the car relative to the ground,

    Vrg for the velocity of the rain relative to the ground,

    and Vrc for the velocity of the rain relative to the car …

    so make a triangle, with an arrow along each side (and be careful to join the sides so that the arrows join correctly!) :smile:
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