Electrostatic Practice

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?

Answer #1 A + B + C – D –

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?

Answer #2 A + B – C – D + E + F –

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

Answer #3 A

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?

Answer #4 Induction Positive Negative

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?

Answer #5 Friction Positive Negative Triboelectric Series

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?

Answer #6 Can A is positive Can C is negative

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?

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

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.

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

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

Answer #9 A

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

Answer #10 B

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.

Answer #11 E

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.

Answer #12 B

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

Answer #13 C

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

Answer #14 A

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

Answer #15 D