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: Physics problem - Real fluids

  1. Apr 30, 2010 #1
    1. The problem statement, all variables and given/known data
    A small block is attached on the left of a larger block by a thin layer of grease, 2 micrometres (10^-6) thick. The mass of the smaller block is 0.15 kg and the area of contact is 8x10^-4 metres squared. If the smaller block slides down 5 mm in 2 weeks, calculate the viscosity of the grease. ANSWER: 9.07x10^5 Pa.s

    2. Relevant equations
    A formula which may help is Force/Area = Viscosity(change in velocity)/distances between areas of contact F/A = (n x delta v)/delta x

    3. The attempt at a solution
  2. jcsd
  3. May 1, 2010 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

    Welcome to Physics Forums.

    That looks like the right equation. Try plugging in the information you are given.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook