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: Friction, Forces, Coefficient of Friction (True/False) Simple

  1. Jan 24, 2009 #1
    1. The problem statement, all variables and given/known data

    You are pushing a filing cabinet across a rough floor (μk = 0.41) in a straight line at a constant speed. Which of the following statements about the magnitudes of the forces acting on the filing cabinet are correct?
    (T/F)the force that you exert on the filing cabinet will be equal to the frictional force on the cabinet
    (T/F) the force that you exert on the filing cabinet will be more than the frictional force on the cabinet
    (T/F)if you exerted twice the force, the cabinet would slide at a constant speed that is twice the original value
    (T/F) the force that you exert on the filing cabinet will be more than its weight
    (T/F)the force that you exert on the filing cabinet will be less than its weight

    2. Relevant equations



    3. The attempt at a solution

    1. True I assume because it's at a constant speed
    2. False I assume because then it would be accelerating?
    3. False, I assume it would just be moving faster and accelerating not at constant speed
    4. No idea
    5. No idea

    Help please, some explanations too would be great. I really appreciate it.
     
  2. jcsd
  3. Jan 24, 2009 #2
    The expression for frictional force is

    [tex]f_k=\mu_k\mbox{N}[/tex]

    N is the normal force and in this case is equal to the weight of the cabinet. This information should help you with the last two questions.
     
  4. Jan 24, 2009 #3
    Sweet, sometimes I'm a little slow, those last two were easy :P
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook