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!

A projectile of mass 1.100 kg is shot straight up with an initial speed of 29.0 m/s.

  1. Oct 24, 2004 #1
    Hello ! Wow, you guys are awesome, Thanks for all the help ! I've got another one I'm stuck on - ... I got part A.. the answer is 42.9082, but I can't get part B... ? help pleaaseee? thaaanks

    A projectile of mass 1.100 kg is shot straight up with an initial speed of 29.0 m/s.
    (a) How high would it go if there were no air friction?
    m
    (b) If the projectile rises to a maximum height of only 35.2 m, determine the magnitude of the average force due to air resistance.
    N
     
  2. jcsd
  3. Oct 24, 2004 #2

    T@P

    User Avatar

    Use the second law of newton: You would have -mg - Fr = ma

    similarly, by the kinematic equations, you can find aceleration by using a system of equations: v = v0 + at and x = x0 + v0t + (1/2)at^2

    in the first, v is o since at the top the velocity is o, you really have two equations with two uknownsl; t and a.

    once you have "a" you can use -mg - Fr = ma or Fr = mg-ma

    Hope i was some help here. (tell me if i did something wrong, i make mistakes sometimes)
     
  4. Oct 24, 2004 #3
    hm.. i didn't really understand what u said at all.. how am i supposed to find a when i dont know t ? ah, confused
     
  5. Oct 24, 2004 #4

    T@P

    User Avatar

    its a system of equations that gets you t and a. The systems are
    -29 = at
    35.2 = 29t + (1/2)at^2
    these two help you solve for a AND t (not that you need t)
    does that help?
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: A projectile of mass 1.100 kg is shot straight up with an initial speed of 29.0 m/s.
Loading...