Lab3 - Physics 272Lab Lab 3 Charge on Tape Lab#3 Charge on...

Physics 272Lab Lab 3: Charge on Tape
Lab #3 – Charge on Tape
OBJECTIVES
In this lab you will:
 Design an experiment to calculate the amount of charge on a piece of tape
 Make physical measurements and modeling assumptions
 Calculate physical quantities based on the above measurements
 Verify your results to be physically reasonable
1) Warm-Up Problems
The following problems are intended to motivate a possible experimental design for measuring the charge
on a piece of invisible tape. After you have taken all necessary data (for your experiment) you will do
calculations similar to those you are about to do in these problems. Therefore, to save your group a great
deal of time in this lab, we advise that you SOLVE THE PROBLEMS BELOW ENTIRELY
SYMBOLICALLY . This symbolic approach will provide you with a formula in which to enter your
experimental data.
Problem (1) Two small plastic balls (of mass ) are rubbed all over with fake fur – both
acquiring the same amount of charge. Attached to each ball are insulating nylon strings, which are
arranged so that the balls may only move up or down in the vertical direction. When one ball is held