Physics Web Search: Electricity
Part I
1. Go to http://phet.colorado.edu/en/simulation/balloons or Google “PHET balloons”
2. Check “Show all Charges.” Nothing else should be checked.
3. Rub the balloon on the shirt
a. What overall charge does the balloon now have?
b. What overall charge does the shirt now have?
c. Move the balloon away from the sweater and let go of the balloon. What happens?
Why?
4. Reset and Check “Wall”
5. Rub the balloon on the shirt again.
a. Move the balloon slowly towards the wall. What happens to the negative charges in the wall?
b. What happens to the positive charges in the wall when you move the balloon near it?
c. Why don’t all the positive charges move toward the balloon?
d. Hold the balloon in between the wall and shirt and release the balloon. What happens to the released
balloon?
e. Why doesn’t the balloon just stay in the middle?
Part II
1. Go to http://phet.colorado.edu/en/simulation/travoltage or google “ PHET Travoltage”
2. Experiment with rubbing Travolta’s foot against the carpet and touching his finger to the door handle.
3. Move his finger far away from the door (not touching the door) and try building charge.
a. What happens?
b. What do the blue circles symbolize, electrons or protons? [ electrons / protons ]
c. Add more blue circles and then pause and watch where the circles move.
i. Do they stay in his feet? [ yes / no ] Where do they move?
d. Why do the blue circles (electrons) move away from each other?
Physics
electrostatic web lab blue
edited4/25/2011
e. Slowly move Travolta’s hand towards the door knob.
i. Shockingly, what happens to the electrons in Travolta when the spark occurs?
ii. Why do the electrons leave Travolta and go to the door handle?
iii. Refer to 5a in the balloon section (Part 1) and recall the electrons moved away from the
negatively charged balloon. When Travolta’s finger is near the door knob and before the
shock discharges Travolta, what happens to the electrons currently in the metal door knob?
iv. Sketch the + and – in the door knob.
4. Try building up charge while Travolta’s finger is on the door.
a. Where do the blue circles (electrons) go?
5. If you take your hat off on a dry winter day, sometimes your hair will stand up. Explain this phenomenon
and sketch charges on Einstein below to help with explanation.
Physics
electrostatic web lab blue
edited4/25/2011