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!

Normal force of the box

  1. Sep 19, 2013 #1
    A 10.0-kg box is placed on top of the 19.0-kg box, as shown in the figure. Determine the normal force that the 19.0-kg box exerts on the 10.0-kg box.

    i know what the normal force of the 19 kg box. i am having problem setting these kind of problems.
     
  2. jcsd
  3. Sep 19, 2013 #2

    SteamKing

    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

    What happens to the 10 kg box if the normal force is greater than 10 kg * 9.81 m/s^2 ?

    What is the normal force on the 19 kg box with the 10 kg box sitting on top?
     
  4. Sep 19, 2013 #3
    it would me greater then the mg right so the Fnet wouldn't be zero?

    Would it the normal force of the two boxes or together?
     
  5. Sep 19, 2013 #4

    SteamKing

    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

    If the normal force is greater than the weight of the box, the box will want to travel upward, F = ma and all that.

    These types of problems are best analyzed by drawing free body diagrams of the boxes and applying the known forces to them. Once that is accomplished, the equations of equilibrium can be written and solved.
     
  6. Sep 20, 2013 #5
    so mg would be downward on both of the boxes and the normal force would be upward for both right?
     
  7. Sep 20, 2013 #6
    so would the normal force being exerted be 98.0N?
     
  8. Sep 20, 2013 #7

    haruspex

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member
    2016 Award

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

Have something to add?
Draft saved Draft deleted