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!

Pressure~gas law

  1. Jun 23, 2013 #1
    1. The problem statement, all variables and given/known data
    rain is falling normally on a circular region of radius 25cm at a rate of 1.2gs-1
    suppose the velocity of each raindrop just before it reaches the region is 10cms-1
    and the collision between each raindrop and the region is perfectly elastic
    find the avg pressure exerted on the region

    take g=9.8ms-1


    2. Relevant equations

    P= F/A

    3. The attempt at a solution

    momentum, then the Pressure
    is it ...P = (0.0012X10+0.0012X9.8) / 0.25^2 pi??
     
  2. jcsd
  3. Jun 23, 2013 #2

    Andrew Mason

    User Avatar
    Science Advisor
    Homework Helper

    If the collisions are perfectly elastic, what is the change in momentum of a raindrop of mass m striking this area?

    Now take N such raindrops every second such that Nm = 1.2 g. What is the total change in momentum of the raindrops every second? How is that change in momentum every second related to the force imparted to the circular area? What is that force/unit area?

    AM
     
  4. Jun 23, 2013 #3
    can i take t=1
    then mv-mu/t = F can be count
    then mass = 1.2 X 1
    then Pressure (P) can be count
     
  5. Jun 23, 2013 #4

    ehild

    User Avatar
    Homework Helper
    Gold Member

    If you use the units and parentheses properly, the method will work. What is u if the collision is perfectly elastic?

    ehild
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Pressure~gas law
  1. Gas Pressure Law (Replies: 1)

Loading...