Name
Date
Pd
Simulation Lab 2 - Electric Field Hockey
Open the Electric Field Hockey Simulation at http://phet.colorado.edu/en/simulation/electric-hockey . After
opening the application you will be viewing the practice screen. On the screen you should see a hockey puck
that has a positive charge. To the top right of the screen you should see 2 bins of positive and negative charge.
You are able to take charges out of these bins and place them on the hockey surface with the puck. These
charges will then interact with the puck. The instructions that follow lead you through investigations with the
puck and charges. Use the simulation to answer the questions.
1. Take a positive charge out of the bin and place it on the surface at the far left edge so it is in line with
the positive puck and the goal on the right. Draw below what you see on the screen. What do you think
the arrow represents?
2. Now move that positive charge so it is half as far away from the puck as it was before (you will be
cutting the distance between the charges in half). Draw below what you see on the screen. How does the
arrow for #2 compare to the arrow in #1? What are the implications of this result based on what we
learned in the sticky tape activities?
3. Now take a second positive charge out of the bin and place it on top of the first positive charge. Draw
below what you see on the screen. What was the effect of adding this second positive charge?
4. Place the positive charges back in the bin. Next, take a negative charge from the bin and place it to the
left of the charged puck so the arrow that appears just reaches the edge of the screen. Draw below what
you see on the screen. What does the arrow represent?
5. Next, take out a positive charge from the bin and place it on top of the negative charge. Draw below
what you see. What was the effect of placing the positive charge on the screen at that location? If you
click the Start button the hockey puck will move based on your placement of the charges. What will
happen to the hockey puck if you click Start based on the current placement of charges? Why?
6. Replace both charges in the bins. Now try to place 2 more charges in a different location such that
clicking the Start button results in no motion of the hockey puck. Draw the configuration that gives this
result below.
7. Return these charges to the bins. Next, place a negative charge on the very left edge of the screen in line
with the hockey puck and the goal. Then place a positive charge half way between the negative charge
and the puck. Draw below what you see on the screen. Which way will the puck begin to accelerate (if at
all) when you click the Start button? Explain why.
8. Next, place a second negative charge on top of the first negative charge at the very left edge of the
screen. Draw below what you see on the screen. Which way will the puck begin to accelerate (if at all)
when you click the Start button? Explain why.
Electric Field Hockey Post-Game Analysis
1. Which direction do electric field lines point for positive charges?
2. Which direction do electric field lines point for negative charges?
3. What do the direction and strength of the field lines indicate for the (positively charged) “puck?”
4. Did the (positively charged) puck always move in the same direction as the field lines it was passing
over?
5. What happened (or would happen) if you changed the charge of the puck from positive to negative? (Try
this!)
6. What happened when you increased the mass of the puck? (Try this!)
7. How did the distance between the puck and the particles affect the motion of the puck? (Experiment,
please!)
8. The field lines on the program are evenly spaced, with darker shades of grey indicating a stronger field.
This is a very clear way of presenting this information. However, it is not what we will normally use.
Why do you think that is?