Electric Field Hockey
We will have already discussed the basics of the concept to include protons, electrons, neutrons, their charges, and what causes them to attract or repel. A review of polarization, insulation and conduction will also be done. These reviews will be a brief concept check before we begin the lab. I will utilize the response cards we have labeled A, B, C, and D and ask questions and have the students hold up the card that corresponds to the answer.
2 Indepenent Practice
The lab will already be set-up with the materials as well as tablets to continue with the PhET simulation. Students will get into their lab groups and move to their stations. There they will find all the instructions to complete the lab for the day as well as instructions for the Electric Field Hockey simulation. As this is my honors class, they are supposed to begin and work independently which allows me to move about and check on all students’ progress and answer any questions.
Blow up the balloon and tie off the end. Put a mark on one side of the balloon. This dot lets you know which area you rubbed.
Rub the balloon with the wool at the dot.
Put the non-charged (away from the dot) part of the balloon near the pieces of paper and the cereal. Observe what happens.
Put the charged (near the dot) part of the balloon near the pieces of paper and cereal. Observe what happens. If nothing happens in this case, vary the distance between the balloon and cereal.
Rub the dot again and try to stick the balloon on different walls on the charged and non-charged parts of the balloon: Concrete, glass, metal, plastic. Observe what happens.
Put the un-charged and charged part of the balloon near a small water stream from the faucet. Observe what happens.
What happened when you put the balloon near the cereal and paper? Was it any different for the side of the balloon with the dot?
Could you get the balloon to stick on all of the different types of walls? How about the part of the balloon not near the dot?
Did the balloon attract the water near the dot? Away from the dot?
From these experiments, what can you say about how charged objects affect regular neutral objects like paper, walls, and water?
Why did we pick less heavy things like paper and cereal in our test rather than something heavy like a pen or a pencil?
After all of your observations, do you know now whether charged objects can attract neutral objects?
Have the students shake out some salt and pepper on a white sheet of paper (no more than a teaspoon each).
Use a pencil's eraser top or pen top to mix the salt and pepper together.
Take the plastic ruler/rod and rub it with the wool/fake fur.
Approach the salt and pepper very slowly with the ruler from above. Observe what happens.
Explain what happens after you rub the ruler.
Why does that happen?
Why did the pepper jump to the ruler before the salt?
Can you think of other ways to separate this mixture?
Blow-up the balloons, tie the ends in a knot, and tie thread to the ends of each balloon.
Tie the balloons together using the thread so the balloons are about 80 cm apart.
Have one person hold the uncharged balloons by the thread and move the balloons together. Record observation.
Rub each balloon all over with the wool as best as possible. Move one balloon near the other but do not allow them to touch. How do they react with each other? Record observations.
While the balloons are repelling each other, have the students gently mist the balloons with water.
Why did the balloons repel each other after they were rubbed all over with the wool?
What would have happened if we rubbed one side of the balloons instead of all over?
Why did the balloons fall back towards each other after they were sprayed with water?
What effect does damp weather have on electrical charges?
During which time of the year would it be best to do experiments using static electricity?
After completing these labs, work independently and access the PhET lesson “Electric Field Hockey” at: https://phet.colorado.edu/en/simulation/electric-hockey
You must run all the levels and record your observations on how the puck moves, placement of + and – charges, the changes made once the barriers began, how are you predicting the movement of the puck, and how the arrows changed when you make the puck a negative charge. Create a table or some other visual to record your data.
Students will be instructed that the PhET lesson may be finished at the beginning of class tomorrow if they need more time.
If all are done, we will begin going over questions and assessing understanding of objectives.