Creative Commons License Copyright © Michael Richmond. This work is licensed under a Creative Commons License.

How tall is your classmate?

Your goal in this experiment is to determine the height of the reach of the tallest student in your group. Your tool: a stopwatch.

  1. Have the tallest student hold a ball in one hand, reaching up as far as he can. On the count of three, he should release the ball so that it falls to the floor.

  2. The other students will measure the time it takes for the ball to fall to the floor. Write down the times.

  3. Repeat for a total of five trials.

  4. Compute the average time, and the uncertainty in that time. Write these down.

  5. Use kinematics to turn the time into a distance the ball travelled -- and its uncertainty. Show your method clearly.

After you've found the distance using kinematics, use a meter stick to measure the actual height of the ball as it is held in the student's hand. Write down this actual height and its uncertainty.

Are the kinematic and actual heights the same, to within their uncertainties?

Creative Commons License Copyright © Michael Richmond. This work is licensed under a Creative Commons License.