Static Electricity Partner Practice

Name:

1. a. A student did their laundry and four (4) objects became charged after a trip through the dryer. A shirt attracts some underwear but repels a sock; the sock attracts a pair of nylons; and we know the nylons have a negative charge. What is the charge on the underwear? How do you know?

b. Why do clothes often come out of the dryer with excess charge?

2. On the blanks below, place the letter of the diagram that best represents the charge and its position on an electroscope during each of the procedures describes.

I. A positively charged rod is brought near the top of an uncharged electroscope but does not touch the electroscope. II. A glass rod is charged positively by rubbing it with silk. The silk is then touched to the top of a neutral electroscope. III. A positively charged rod is brought near a neutral electroscope, and the electroscope is charged by induction. IV. An electroscope is charged by conduction using a positively charged rod. V. A negatively charged rod is brought near a neutral electroscope but does not touch it. VI. A positively charged rod is brought near a positively charged electroscope. What would you change to make the drawing a little more accurate in this case?

VII. A metal rod is brought in contact with the positively charged electroscope. What is special about metal?

3. Oil drips slowly from a narrow dropper inside but not touching a negatively charged metal ring.

a. Before the dropper releases a drop, will there be a charge on them? If so, what charge and why? If not, why not?

b. As the drops fall through the metal ring (without touching it), will there be a charge on them? If so, what charge and why? If not, why not?

The drops fall through the metal ring (without touching it) into a metal can that is on an insulating plastic platform. c. Will the drops transfer a charge to the metal can? If so, what charge and why? If not, why not?

4. Two negatively charged balloons repel each other; one is blue and the other green. Determine what would happen to the size of the repulsion force in each case (increase or decrease or remain the same) and explain why. Assume each case is independent of the others. a. The blue balloon is given even more negative charge than it had before.

b. The blue and green balloons are both given even more negative charge than they had before.

c. The blue balloon is brought closer to the green balloon.

d. The distance between the blue and green balloon is doubled.

e. The blue and green balloons both double their negative charge and the distance between them is doubled.