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!

Help me figure out where this equation was derived

  1. Jan 27, 2010 #1
    1. The problem statement, all variables and given/known data

    A placekicker must kick a football from a point 36.0 m (about 40 yards) from the goal, and half the crowd hopes the ball will clear the crossbar, which is 3.05 m high. When kicked, the ball leaves the ground with a speed of 23.0 m/s at an angle of 46.0° to the horizontal.

    I have completed the problem correctly but was told to find time by t= delta x / (vi *costheta)

    Where is this equation derived from is what i'm asking?

    thanks
     
  2. jcsd
  3. Jan 27, 2010 #2

    Mentallic

    User Avatar
    Homework Helper

    The time (t) it takes for something with uniform speed (u) to complete some displacement ([itex]\Delta x[/itex]) is given by [tex]t=\frac{\Delta x}{u}[/tex]. But the problem is that the uniform speed isn't quite the initial velocity of the ball. The ball is projected at an angle to the horizontal, so can you figure out what the horizontal velocity of the ball is?
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Help me figure out where this equation was derived
  1. Pls help me figure out (Replies: 1)

Loading...