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!

An athlete executing a long jump leaves the ground at a 29.5

  1. May 21, 2015 #1
    1. The problem statement, all variables and given/known data
    An athlete executing a long jump leaves the ground at a 29.5∘ angle and travels 7.69m . A- What was the take off speed? B- If this speed were increased by just 4.0%, how much longer would the jump be?

    2. Relevant equations- Unfortunately I'm totally stuck and I'm not sure what equations to use for this


    3. The attempt at a solution - I can't come to any solution because I don't really understand where to begin with this problem..
     
  2. jcsd
  3. May 21, 2015 #2

    Svein

    User Avatar
    Science Advisor

    What you know is:
    • In the jump phase, the only force is g which pulls the athlete down
    • The start angle tells you which part of the take off speed goes upward
    • ... and which part goes forward
    • When the height above ground is 0 (again), the athlete lands
    • And you are supposed to know the formula for distance given speed and accelration
     
  4. May 21, 2015 #3

    haruspex

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member
    2016 Award

    G**gle SUVAT.
     
  5. May 21, 2015 #4
    I'm sorry, but I have no idea what that means. I just started Physics for the first time a few days ago, and am having a very hard time
     
  6. May 21, 2015 #5

    haruspex

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member
    2016 Award

    Well, if you had searched the net for SUVAT, as I suggested, you might well have found this, for example: http://en.wikipedia.org/wiki/Equations_of_motion.
    Searching for suvat in that page would bring you to http://en.wikipedia.org/wiki/Equations_of_motion#Uniform_acceleration.
    However, that reference is not quite ideal because it fails to point out that you can solve a problem such as yours by analysing horizontal and vertical motion separately. That is, you apply the 1-dimensional equations ("collinear" there) in the horizontal and vertical directions separately. To do this, you have to know how to resolve a velocity into its horizontal and vertical components.
    There are lots of other hits for SUVAT. See which you find the most intelligible. This will be much more efficient than people on this forum trying to teach it to you. But, if there's any specific statements in them you need to have more explanation on, I'll see what I can do.
    You might also find this useful, once you have the basics: https://www.physicsforums.com/insights/frequently-made-errors-mechanics-kinematics/
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: An athlete executing a long jump leaves the ground at a 29.5
  1. Long Jump Question (Replies: 16)

  2. Physics of a Long Jump (Replies: 7)

  3. Long Jump (Replies: 1)

Loading...