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!

Homework Help: Impulse on a sliding block attched to spring

  1. Jan 23, 2009 #1
    A 4kg wooden block resting on an icy surface (so friction can be ignored) is attached to a horizontal spring (L=1m, k=100N/kg), which is attached on the other end to a vertical wall. A 2g bullet is fired at a speed of 100m/s into the wooden block, pushing it directly toward the wall. What is the period and amplitude of the resulting oscillations?


    I have no clue?
  2. jcsd
  3. Jan 23, 2009 #2
    Re: Oscillation

    A good starting point would be to calculate how much energy the bullet transfers to the spring-block system.

    Also (I'm sure it was a typo, but) the spring constant, [itex]k[/itex], can never take the value N/kg. [itex]k[/itex] is a measure of restoring force per unit length of displacement, so the S.I. unit is N/m.
  4. Jan 23, 2009 #3
    Re: Oscillation

    okay... I got T=1.2s and A=45cm ... is this correct?
  5. Jan 23, 2009 #4


    User Avatar
    Homework Helper

    Re: Oscillation

    Not sure how you arrived at your amplitude. Your period looks about right, though I would check to see that you rounded correctly.
  6. Jan 23, 2009 #5
    Re: Oscillation

    Looks good to me. (Just to be pedantic, [itex]\tau[/itex] is closer to 1.3 s than 1.2 s, but you obviously got the correct answer!)
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook