Lab 3: Motion in an Electric Field
In this lab you will use PhETs simulation Electric Field Hockey to study the motion of a charged particle in the electric field produced by discrete charge distributions.
Note: Unlike previous simulations, this is not an HTML5 simulation. This means it might not work
on some browsers. Please try a different browser if the simulation does not start (after a little wait).
The path of motion of the charged puck depends on its mass (which you can change by using a
slider in the simulation), the initial conditions (the puck will always start from rest when you reset
the simulation), and the electric field. In this simulation we will produce the electric field using
point charges. The objective is to find a static charge distribution that makes the charged puck
move around the obstacle(s) and reach the goal. Static means you will not be moving the charges
that generate the electric field after you start the simulation.
1. Select the checkboxes for Trace and Field to visualize the path of motion of the charged
puck and the electric field.
2. Start with the Practice and a positively charged puck. What is the simplest solution to move
the puck and score a goal? Take a snapshot of the simulation showing that you scored a
goal. Explain the path of motion.
3. Now, select Difficulty level 1. Find a simple charge distribution that allows the puck to move
around the obstacle and into the goal. Take a snapshot of the simulation showing that you
scored a goal. Explain the path of motion. How do you need to modify your charges without
changing their positions to score a goal with a negatively charged puck? Test your
hypothesis.
4. Repeat the previous step for Difficulty levels 2 and 3 only with a positively charged puck.
Include your snapshots showing your successes (as well as a description of your failed attempts) in
the Measurements and Observations section of your report. Your explanations of the path of motion
of the puck should be included in the Data Analysis and Discussion section. Make sure you adhere to
other requirements of the lab report as well.
