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: Arrow goes into block

  1. Jan 23, 2008 #1
    1. The problem statement, all variables and given/known data
    An arrow is fired with a speed of 22.0 m/s at a block of Styrofoam resting on a smooth surface. The arrow penetrates a certain distance into the block before coming to rest relative to it. During this process the arrow's deceleration has a magnitude of 1570 m/s^2 and the block's acceleration has a magnitude of 450 m/s^2.
    a)How long does it take for the arrow to stop moving with respect to the block?
    b)What is the common speed of the arrow and block when this happens?
    c)How far into the block does the arrow penetrate?

    2. Relevant equations
    I tried doing a= v/t. to find the time. but the answer wasnt right. i really dont know where to start for it.

    3. The attempt at a solution
    I need help on parts a and b. i really have no ideas what to do.
    Last edited: Jan 23, 2008
  2. jcsd
  3. Jan 23, 2008 #2
    i just need a formula to get going.
  4. Jan 23, 2008 #3

    Shooting Star

    User Avatar
    Homework Helper

    For arrow, v= u -a1*t. For block, v = 0 + a2*t. You find v and t. Enough?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook