Lab 3:

Winter 2004


Two-Dimensional Momentum Conservation

Consider the multiflash photograph of a collision of two billiard balls. Assume that the time interval between flashes is .1 second. Do the measurements below reasonably carefully.

  1. Choose a coordinate system. (A clever choice will make the problem a little easier.)
  2. Determine the velocity vectors for each of the balls before and after the collision. Write the vector as both a magnitude and direction and in component form.
  3. Determine the momentum of the system before and after the collision. Write your answer as both a magnitude and direction and in component form.
  4. Is momentum conserved?


Dimensional Analysis

From P. Tipler, Physics for Scientists and Engineers, Third edition, Worth Publishers, 1991.
  1. The period T of a simple pendulum depends on the length L of the pendulum and the strength of earth's gravitational field g. Find a simple combination of L and g that has the dimensions of time.
  2. Check the dependence of the period T on the length L by measuring the period for three different values of L. (The period T is defined as the time for a complete to-and-fro swing.)
  3. The correct formula involves a numerical factor that is dimensionless and hence can't be obtained by dimensional analysis. Using your data from the above question, estimate the value of the numerical factor.




[Dave] [Physics I] [COA]

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