1. PF Contest - Win "Conquering the Physics GRE" book! Click Here to Enter
    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!

Pressure of Crutches

  1. May 2, 2012 #1
    1. The problem statement, all variables and given/known data

    A 72 kg person sits on a 4.0 kg chair. Each leg of the chair makes contact with the floor in a circle that is 1.1 cm in diameter. Find the pressure exerted on the floor by each leg of the chair, assuming the weight is equally distributed.

    2. Relevant equations


    3. The attempt at a solution

    To find the force, I added the mass of the person and the mass of the chair and got m=76kg. Then i multiplied that by g=9.81 and got F=745.56.
    To find the area, I converted 1.1 cm into meters, .011, and found the area A=9.5*10^-5
    then i divided F/A and got P=7845260 but this is incorrect.
  2. jcsd
  3. May 2, 2012 #2


    User Avatar
    Science Advisor

    Okay, that's good.

    Did you recall that the chair has four legs? Oh, and be sure to include units of measurement.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Threads - Pressure Crutches Date
Pressure problem Mar 8, 2018
Pressure and volume question Mar 3, 2018
Force on a Door Feb 7, 2018
Hydrostatic pressure in a tilted tube Feb 1, 2018