Question 1

You and a friend are spending the weekend making up missed lab experiments. You are on to second - semester material and are studying the electrostatic interaction of two charges. You notice that two charges are exerting a certain force on one another. If the distance between two electric charges doubles, then the force they exert on each other changes by how much?

Accepted Answer

The force between two charges is given by Coulomb's law, which states that the force is inversely proportional to the square of the distance between the charges. Therefore, if the distance doubles, the force becomes $1/4$ as large.

Question 2

You and a friend are spending the weekend making up missed lab experiments. You are on to second - semester material and are studying the electrostatic interaction of two charges. You notice that two charges are exerting a certain force on one another. If the distance between two electric charges becomes 1/3 of what it originally was, then the force they exert on each other changes by how much?

Accepted Answer

The force between two charges is given by Coulomb's law, which states that the force is inversely proportional to the square of the distance between the charges. If the distance is reduced to 1/3 of its original value, the force becomes (1/(1/3)^2) = 9 times as big.

Question 3

A positive charge and a negative charge will

Accepted Answer

Opposite charges attract each other according to Coulomb's law.

Question 4

You and a friend are spending a weekend at a carnival. You get bored and begin to make electrostatics measurements. It turns out that you have a charge of +3 Coulombs and your friend a charge of -5 Coulombs. What is the net electric charge?

Accepted Answer

The net electric charge is the sum of the charges: +3 Coulombs + (-5 Coulombs) = -2 Coulombs.

Question 5

Who originally named electric charges as positive and negative?

Accepted Answer

Benjamin Franklin was the one who originally named electric charges as positive and negative. He did this in the 18th century as part of his experiments with electricity, where he proposed the theory of one fluid where electricity could be seen as an excess or deficiency of this fluid, thus coining the terms positive and negative for these conditions.

Question 6

You stick two pieces of adhesive tape on a glass window and then pull them off suddenly. If you now hold the tape pieces near each other, they will be

Accepted Answer

The answer of You stick two pieces of adhesive tape...

Question 7

Which of the following can cause a charged particle to accelerate?

Accepted Answer

An electric field can cause a charged particle to accelerate due to the electric force acting on the charge. Similarly, a gravitational field can cause any particle with mass, including charged particles, to accelerate due to gravitational force. A neutron field, however, does not exert a force on charged particles that would cause acceleration.

Question 8

If an electron and a proton both experience the same electric force,

Accepted Answer

The electron will have greater acceleration because it has much less mass than the proton, and acceleration is inversely proportional to mass when the force is constant (F=ma).

Question 9

After running a plastic comb through you hair several times you hold it above a small scrap of paper. The paper jumps off the table and sticks to the comb because the paper becomes

Accepted Answer

The comb becomes electrically charged through friction with the hair, and when it is brought near the paper, it induces a separation of charges within the paper, causing it to become electrically polarized. This polarization results in an attractive force between the comb and the paper.

Question 10

You have just pulled your clothes from the dryer and find that a sock is clinging to your jeans with static electricity. You hold the jeans in one hand and the sock in the other and pull the two apart. As jeans and sock move apart, the forces between them become weaker because the

Accepted Answer

The forces between the jeans and the sock become weaker as they move apart due to the increase in distance between them, which reduces the strength of the electrostatic attraction according to Coulomb's law.

Question 11

A charged object is able to attract

Accepted Answer

The answer of A charged object is able to attract
...

Question 12

Suppose you have two identical socks that exert a force of 10 N on each other. Now you move them so they are three times as far apart as they were originally.
-Calculate the new force between the objects.

Accepted Answer

The answer of Suppose you have two identical socks that...

Question 13

Suppose you have two identical socks that exert a force of 10 N on each other. Now you move them so they are three times as far apart as they were originally.
-Will this force be attractive or repulsive? Please explain.

Accepted Answer

The answer of Suppose you have two identical socks that...

Question 14

Your instructor staggers into class after a classic party. He does a demonstration in class where he measures a force of attraction between two positively charged spheres to be 12N when they are 5m apart and then claims that the force is 24N when they are 10m apart. Specific to the demonstration, please list and briefly describe three reasons why his claims must be wrong. One of your three points must be quantitative (must involve some type of force calculation).

Accepted Answer

The answer of Your instructor staggers into class after a...

Question 15

Suppose your instructor staggers into class the morning after an all-night 4x4 truck engine pulling party. She proceeds to do a demonstration in class where she measures a 100N force of attraction between two particles each carrying a positive charge of 1C and separated by 3m. Moreover she cuts the distance to ¼ of what it originally was and she claims the force then changes to a new value of 25N. Specific to the scientific content of her demonstration please give three reasons why you know that her claims are wrong; there's more than three, trust me. One of your three points must be quantitative - involving a force calculation of some sort.

Accepted Answer

The answer of Suppose your instructor staggers into class the...

Question 16

Suppose you are given two metal spheres on insulating stands, a plastic rod and some fur that you can rub the rod with to charge the rod. You cannot touch the spheres to ground using a wire, finger, etc. - you can just move them around using the insulated stands and touch them with the rod. They may touch each other if need be.
-Starting with both spheres neutral please describe how you would give the spheres equal net charges of the same sign.

Accepted Answer

The answer of Suppose you are given two metal spheres...

Question 17

Suppose you are given two metal spheres on insulating stands, a plastic rod and some fur that you can rub the rod with to charge the rod. You cannot touch the spheres to ground using a wire, finger, etc. - you can just move them around using the insulated stands and touch them with the rod. They may touch each other if need be.
-Starting with neutral spheres please describe how you would give the spheres equal and opposite charges.

Accepted Answer

The answer of Suppose you are given two metal spheres...

Question 18

Suppose you have two identical socks that repel each other with a certain force. Now you move them so they are three times as far apart as they were originally, but the force between them stays the same.
-What is one way in which the charges might change so the force could remain constant?

Accepted Answer

The answer of Suppose you have two identical socks that...

Question 19

Suppose you have two identical socks that repel each other with a certain force. Now you move them so they are three times as far apart as they were originally, but the force between them stays the same.
-In this case, let the charges remain the same as the socks separate so that the force decreases as they are separated. In moving the socks apart did the potential energy increase or decrease? Please explain.

Accepted Answer

The answer of Suppose you have two identical socks that...

Question 20

An atom under no external influences may be thought of as a positively charged nucleus surrounded by a negatively charged electron cloud. Now suppose the atom is placed in a uniform external electric field (like you'd find between two parallel charged plates). Please explain why this would stretch the atom out, elongating it.

Accepted Answer

The answer of An atom under no external influences may...

Quiz 10: Electricity

A positive charge and a negative charge will

You and a friend are spending a weekend at a carnival. You get bored and begin to make electrostatics measurements. It turns out that you have a charge of +3 Coulombs and your friend a charge of -5 Coulombs. What is the net electric charge?

Who originally named electric charges as positive and negative?

You stick two pieces of adhesive tape on a glass window and then pull them off suddenly. If you now hold the tape pieces near each other, they will be

Which of the following can cause a charged particle to accelerate?

If an electron and a proton both experience the same electric force,

After running a plastic comb through you hair several times you hold it above a small scrap of paper. The paper jumps off the table and sticks to the comb because the paper becomes

You have just pulled your clothes from the dryer and find that a sock is clinging to your jeans with static electricity. You hold the jeans in one hand and the sock in the other and pull the two apart. As jeans and sock move apart, the forces between them become weaker because the

A charged object is able to attract

Suppose you have two identical socks that exert a force of 10 N on each other. Now you move them so they are three times as far apart as they were originally. -Calculate the new force between the objects.

Suppose you have two identical socks that exert a force of 10 N on each other. Now you move them so they are three times as far apart as they were originally. -Will this force be attractive or repulsive? Please explain.

Suppose you have two identical socks that repel each other with a certain force. Now you move them so they are three times as far apart as they were originally, but the force between them stays the same. -What is one way in which the charges might change so the force could remain constant?