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!

Two Blocks At Top Of Hill

  1. Sep 15, 2009 #1
    1. The problem statement, all variables and given/known data

    A 1-lb block and a 100-lb block are placed side by side at the top of a frictionless hill. Each is given a very light tap to begin their race to the bottom of the hill. In the absence of air resistance, what can you conclude about the outcome of the race?


    2. Relevant equations



    3. The attempt at a solution

    This is a multiple choice question. Here are the choices:

    1) The 1-lb block wins the race.
    2) The 100-lb block wins the race.
    3) The two blocks end in a tie.
    4) There’s not enough information to determine which block wins the race.


    We haven't learned the mathematics behind this question yet. It's a conceptual question. I was thinking, since the hill is frictionless, the 100-lb block should have more force going down the hill than the 1-lb, so I figure that the 100-lb block should win the race. I'm not too confident in my answer though...
     
  2. jcsd
  3. Sep 15, 2009 #2

    rl.bhat

    User Avatar
    Homework Helper

    In the absence of air resistance and friction, all the objects will have the same acceleration during free fall. It is independent of mass. Sliding down from a hill top is also a free fall.
     
  4. Sep 15, 2009 #3
    To add to what rl.bhat said, check out this link (http://www.physicsclassroom.com/Class/vectors/u3l3e.cfm). Since you said you haven't learned how to do this yet, it is hard to explain why using equations, so maybe this will help.
     
  5. Sep 15, 2009 #4
    So the race will be a tie?
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook