Go to http://phet.colorado.edu/simulations/sims.php?sim=Electric_Field_Hockey
and click on Run Now.
1. You rub balloons in your hair and then hang them like in the picture below. Explain why you think they move apart and what might affect how far apart they get. A balloon becomes negatively charged when it is rubbed on a person’s hair. This occurs because all the protons and neutrons leave the balloon and attach to other objects such as the hair. If two balloons both have negative charges then both balloons will repel each other because same charges repel while opposites attract.
2. Test your ideas using Electric Field Hockey in the Practice mode. Make a table to record your observations about what affects the direction and speed of the puck. Your table should demonstrate that you have run controlled tests with all the variables.
|Charges introduced |Effects on positive charge repulsion | |Positive |Repel | |Negative |Attract |
|Charges introduced |Effects on positive charge speed | |Positive |Close to charge=Increasing repulsion speed | | |Far from charge= decreasing repulsion speed | |Negative |Close to charge=Increasing attraction speed |...