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: Mechanics question

  1. Jan 26, 2004 #1
    Suppose I am standing at the top of a cliff which is a vertical distance (d) above the ground. Now, if I jump off the slide at an angle beta upwards at an initial velocity (v), I will travel a horizontal distance of (R). I have proved the first part of the question which shows these quantities are related by the equation:

    Rsin(2beta) + d(1 + cos(2beta))=(R^2)g/v^2

    where g is 9.8 meters per second squared.

    Ok, now here is the relation which I am having problems solving:

    The condition for maximum range R is

    tan(2beta)=R/d.

    I have no idea how to go about showing this. Any ideas or suggestions?
     
  2. jcsd
  3. Jan 26, 2004 #2

    chroot

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

  4. Jan 26, 2004 #3

    Doc Al

    User Avatar

    Staff: Mentor

    Start by taking the derivative with respect to beta of your first relation.
     
    Last edited: Jan 26, 2004
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook