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Deriving A Motion Equation

  1. Feb 24, 2010 #1
    1. The problem statement, all variables and given/known data
    Derive algebraic expressions for the range and total time-of-flight of a projectile launched with initial speed v, from a height h, and at an angle Q, above the horizontal. We were given the final equations but I am unsure of how to derive them.

    2. Relevant equations
    range=vt-.5gt^2, where g is the acceleration due to gravity and t is the time in seconds.

    time= (vsinQ+((vsinQ)^2+2gh)^.5)/g

    3. The attempt at a solution
    Considering the ball, after it has been launched:

    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Feb 24, 2010 #2


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    Homework Helper

    If you were given initial speed 100, angle 30 degrees, height 2 m
    could you solve it? If so, you can just replace the 100, 30 and 2 in every place with the given letters.

    The first step is to find the horizontal and vertical components of the speed.
    Then write equations for the vertical and horizontal motions.
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