1. Electrostatic Practice

2. Question #1 Object A is positively charged.
Object A and Object B repel.
Object B and Object C attract.
Object C and Object D repel.
What are the charges on B, C and D?

3. Answer #1
A +
B +
C –
D –

4. Question #2 Object A is positively charged.
Object A and Object B attract.
Object B and Object C repel.
Object C and Object D attract.
Object D and Object E repel.
Object E and Object F attract.
Object F and a neutral object attract.
What are the charges on B, C, D, E and F?

5. Answer #2
A +
B –
C –
D +
E +
F –

6. Question #3
Two lab partners are doing a static electricity investigation. They begin with a neutral soda can. After conducting the procedure they notice that the can is now charged negatively. Which statement best explains why happened?
a. Electrons were added to the object
b. Protons were added to the object
c. Electrons were removed from the object
d. Protons were removed from the object

7. Answer #3 A

8. Question #4
A neutral metal can is mounted on a foam stand. A negatively charged balloon is brought near. The can is touched on the other side.
1. What is the method used to charge the can?
2. What is the charge on the can after it is touched?
3. What is the charge on the balloon after the can is touched?

9. Answer #4
Induction
Positive
Negative

10. Question #5
A vinyl balloon is rubbed on a wool sweater and then removed.
What is the method used to charge the balloon?
What is the charge on the sweater?
What is the charge on the balloon?
What chart indicates how the electrons are transferred in this scenario?

11. Answer #5
Friction
Positive
Negative
Triboelectric Series

12. Question #6
Three neutral, metal cans (A, B and C) - mounted on insulating stands – are touching. A negatively charged balloon is brought near Can A. Can B is then removed.
What are the charges on Can A and Can C?

13. Answer #6
Can A is positive
Can C is negative

14. Question #7 Object A is positively charged.
Object A and Object B repel.
Object B and Object C attract.
Object C and Object D attract.
Object D and Object E repel.
Object E and Object F repel.
What are the charges on Objects B,C,D,E and F?

15. Answer #7
A +
B +
C – or neutral
D + or –
E + or –
F + or –

16. Question #8
Identify the objects as either +, -, neutral or a combination of the three.
An object possesses more protons than electrons.
An object possesses more neutrons than electrons.
An object attracts neutral paper bits.
An object attracts both a negatively charged balloon and a positively charged balloon.
An object that has field lines directed inward.

17. Answer #8
a. + b. +, - and neutral c. +, - d. neutral e. –

18. Question #9 As an object acquires a positive charge, its mass usually
decreases
increases
stays the same
becomes negative

19. Answer #9 A

20. Question #10 To be safe during a lightning storm, it is best to be
in the middle of a grassy meadow
inside a metal car
next to a tall tree in a forest
inside a wooden building
on a metal observation tower

21. Answer #10 B

22. Question #11
Fred the lightning bug has a mass m and a charge of +q. Jane, his lightning bug wife, has a mass of 3/4m and a charge of -2q. Because they have charges of opposite signs they are attracted to each other. Which is attracted more to the other, and by how much?
Fred, twice as much
Jane, twice as much
Fred, four times as much
Jane, four times as much
They are attracted to each other by the same amount.

23. Answer #11 E

24. Question #12
Fred the lightning bug has a mass m and a charge of +q. Jane, his lightning bug wife, has a mass of 3/4m and a charge of -2q. Because they have charges of opposite signs they are attracted to each other. As they move toward each other who is faster and why?
Fred, because he has more mass
Jane, because she has less mass
They both have the same speed because they
feel the same force.

25. Answer #12 B

26. Question #13
A plastic rod is rubbed with a piece of animal fur. The plastic rod acquires a negative charge during this process. Which of the following is true about the charge on the piece of fur?
It acquires a positive charge but greater in magnitude than the rod
It acquires a positive charge but less in magnitude than the rod
It acquires a positive charge with the same magnitude as the rod
It acquires a negative charge but greater in magnitude than the rod
It acquires a negative charge but less in magnitude than the rod

27. Answer #13 C

28. Question #14
Sphere A carries a charge of +2C and an identical sphere B is neutral. Sphere A briefly comes into contact with sphere B. After they are separated what is the charge on sphere B?
+1C
+2C 0C
+4C

29. Answer #14 A

30. Question #15
If the distance between two positive charges is tripled, then the strength of the electrostatic repulsion between them will decrease by a factor of 3 6 8 9 12

31. Answer #15 D