1. Limited time only! Sign up for a free 30min personal 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!

Homework Help: What is the magnitude of the downward force

  1. Apr 9, 2009 #1
    1. The problem statement, all variables and given/known data

    80-kg man balances the boy on a teeter-totter as shown.
    Note: Ignore the weight of the board. What is the magnitude of the downward force exerted on the fulcrum in Newtons?

    2. Relevant equations

    3. The attempt at a solution

    Attached Files:

  2. jcsd
  3. Apr 10, 2009 #2
    Perhaps like this. First we use momentum equations to determine boys weight.
    ΣM=0 mb*g*4=mm*g*1
    Then we use forces equations.
    ΣF=0 mb*g+mm*g-Ff
    Ff=981 N
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook