1. Not finding help here? Sign up for a free 30min 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!

Very simple gravity/time/distance travelled problem

  1. Dec 8, 2009 #1
    1. The problem statement, all variables and given/known data
    This isn't really homework, because I'm not at school anymore (aged 42!) but I will describe as best as I can.

    A small object like a droplet of water is released from a height (point A), falling on the surface (Point B) with initial speed 0. Distance between A and B, I will call d and obviously there's gravity (g) and time it takes for the droplet to fall from A to B, I will call t1. I know the equation so that given d is known, and so is gravity, then I can calculate time (t1).

    Suppose that between points A and B, there's a point X. By the time the droplet has reached X is already has a certain speed. How do I calculate the time (t2) that it takes for the droplet to travel from X to the surface (B)?

    2. Relevant equations

    t1=square_root((2 * d)/g)

    3. The attempt at a solution

    I know (or at least I think I know) that I can't use the same equation to calculate t2 because the droplet already has a certain speed.

    Apologies, if I'm not explaining this very well. I've not done any physics for 25 years and the reason I need this is because I'm doing high speed photography with falling objects.

    thx

    DK
     
  2. jcsd
  3. Dec 8, 2009 #2
    If you know the distance AX, you can use the above equation to calculate the time for the droplet to reach point X, t[X]. As t[1] stays the same whether or not you add an extra reference point, simply substract t[X] from t[1] and you have your answer.

    Hope this helps.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Very simple gravity/time/distance travelled problem
Loading...