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!

Stuck on finding force

  1. Sep 30, 2007 #1
    1. The problem statement, all variables and given/known data

    An adult 68.0kg cheetah can accelerate from rest to 20.1 (45.0mph ) in 2.00 s.

    2. Relevant equations

    Vf=Vi + (a)t

    3. The attempt at a solution

    Assuming constant acceleration, find the net external force causing this acceleration

    i solved for the time using Vf=Vi + (a)t. i got acc=10.05

    when i tried plugging in the 10.05 for the acceleration and times the mass it gave me 684N. Its coming up wrong and I dont know where im messing up on
  2. jcsd
  3. Sep 30, 2007 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    When I multiply 68 by 10.05 I get 683.4. I would guess its just a rounding error.
  4. Sep 30, 2007 #3
    Are you sure its 684. you are messing up with the calculations, i suppose.
  5. Sep 30, 2007 #4
    yea actually did it would let you know if you where close but it says nothing about a rounding error
  6. Sep 30, 2007 #5
    actually no the computer was wrong thanks for the help though it was a glitch in the computer it has 2.01m/s as 45mph so it takes the right answer to be 68.3N. Man that is why I really hate online hw. but thanks anyway
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Stuck on finding force
  1. Finding force (Replies: 9)

  2. Finding force (Replies: 4)

  3. Finding the Force (Replies: 44)

  4. Finding the Force (Replies: 5)