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: Constant acceleration simultaneous equation

  1. Sep 28, 2010 #1
    1. The problem statement, all variables and given/known data
    A pizza is being dropped from a height of 20 m. Another pizza is being thrown up at 30m/s from 0m(the one falling is above the one being thrown). At what position in the air will they meet?

    a= -10m/s^2

    2. Relevant equations
    Im not sure but i think that some of the b5 kinematics equations would apply. Im pretty sure that this requires a simultaneous equation.


    3. The attempt at a solution
    first i had x=viT+1/2aT^2

    i attempted to get all the t's to one side but got stuck at (2x/vi)/a=(t^2)/vi)+2t/a

    i assumed that the t's must be equal. I am unsure whether or not i approached the problem correctly or not
     
  2. jcsd
  3. Sep 28, 2010 #2
    I appreciate you guys for looking at this but i think i got it:
    so basically

    you have two side

    first equation = falling pizza:

    x=0-1/2at^2

    you set that one, equal to your thrown pizza: x=30-1/2at^2

    set them equal to each other, then solve for t then use that t to solve for x
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook