Question 1

Two charges separated by 1 m exert a 1-N force on each other. If the magnitude of each charge is doubled, the force on each charge is

Accepted Answer

The force between two charges is given by Coulomb's law, which states that the force is directly proportional to the product of the magnitudes of the charges and inversely proportional to the square of the distance between them. If the magnitude of each charge is doubled, the product of the charges becomes four times larger (since 2 * 2 = 4), and since the distance does not change, the force becomes four times larger as well. Therefore, the new force is 4 N.

Question 2

A wire that carries an electric current

Accepted Answer

A wire carrying an electric current may or may not be electrically charged. The flow of electric current refers to the movement of electric charge, which can occur in a neutral wire without the wire itself having a net electric charge.

Question 3

A proton and an electron are placed in an electric field. Which undergoes the greater acceleration?

Accepted Answer

The electron undergoes greater acceleration due to its much smaller mass compared to the proton, despite both experiencing the same force in the electric field.

Question 4

An electroscope is charged positively as shown by foil leaves that stand apart. As a negative charge is brought close to the electroscope, the leaves

Accepted Answer

When a negative charge is brought close to a positively charged electroscope, the leaves fall closer together because the negative charge induces a redistribution of charges within the electroscope, causing some positive charges to move towards the top, reducing the repulsion among charges in the leaves.

Question 5

Two charges separated by 1 m exert a 1-N force on each other. If the charges are pulled to a 3-m separation distance, the force on each charge will be

Accepted Answer

The answer of Two charges separated by 1 m exert...

Question 6

Electrons are made to flow in a wire when there is

Accepted Answer

Electrons are negatively charged particles, and they flow from a region of higher electrical potential to a region of lower electrical potential. This difference in potential energy is referred to as a potential difference or voltage, and it is created by connecting the wire to a battery or other electrical source. Therefore, choice C is the correct answer.

Question 7

The electrical force on a 2-C charge is 60 N. What is the value of the electric field at the place where the charge is located?

Accepted Answer

The electric force on a charge is given by the product of the charge and the electric field. Thus, F=qE, where F=60 N and q=2 C. Solving for E, we get E=F/q=60 N/2 C=30 N/C. Therefore, the value of the electric field at the place where the charge is located is 30 N/C, which is choice B.

Question 8

A coulomb of charge that passes through a 6-V battery is given

Accepted Answer

The energy given to a coulomb of charge by a 6-V battery is calculated using the formula energy (in joules) = voltage (in volts) × charge (in coulombs). Therefore, 6 volts × 1 coulomb = 6 joules.

Question 9

An electron is pushed into an electric field where it acquires a 1-V electrical potential. If two electrons are pushed the same distance into the same electric field, the electrical potential of the two electrons is

Accepted Answer

In an electric field, the electrical potential energy gained by an electron is given by the equation U=qV, where U is the potential energy, q is the charge on the electron, and V is the electrical potential. As the two electrons have the same charge, they will both gain the same amount of potential energy when pushed the same distance into the electric field. Therefore, the electrical potential of the two electrons will be the same, which is 1 V.

Question 10

If you use 10 J of work to push a coulomb of charge into an electric field, its voltage with respect to its starting position is

Accepted Answer

The voltage (V) is defined as the work done (W) per unit charge (Q), V = W/Q. Here, with 10 J of work done to move 1 coulomb of charge, the voltage is 10 J/C = 10 V.

Question 11

About how much electrical resistance does the human body have?

Accepted Answer

The answer of About how much electrical resistance does the...

Question 12

Normally a balloon charged to several thousand volts has a relatively small amount of

Accepted Answer

A balloon charged to several thousand volts indeed has a relatively small amount of both charge and energy. The high voltage indicates the potential difference but does not necessarily mean a large amount of charge or energy due to the small capacitance of the balloon.

Question 13

The units used to measure electrical resistance are called

Accepted Answer

Ohms are the units used to measure electrical resistance, symbolized by the Greek letter omega (Ω).

Question 14

Charge carriers in a metal are electrons rather than protons because electrons are

Accepted Answer

Electrons are the charge carriers in metals because they are loosely bound to their atoms, allowing them to move freely through the lattice structure of the metal when a voltage is applied.

Question 15

If you use 10 J of work to push a charge into an electric field and then release the charge, as it flies past its starting position, its kinetic energy is

Accepted Answer

The kinetic energy of the charge as it flies past its starting position would be 10 J, because the work done on the charge is converted into kinetic energy, assuming no energy losses.

Question 16

A charged balloon neatly illustrates that something can have a great amount of

Accepted Answer

A charged balloon can have a high voltage due to the separation of charges on its surface, but the amount of charge (and thus the potential energy) can be relatively small because the balloon itself is small and can only hold a limited amount of charge.

Question 17

To be safe in the unlikely case of a lightning strike, it is best to be inside a building framed with

Accepted Answer

Steel-framed buildings provide a path for lightning to safely ground, reducing the risk of fire or electrical surges, unlike wood, which does not conduct electricity and offers no protection against lightning.

Question 18

Two charges separated by one meter exert a 1-N force on each other. If the charges are pushed to 0.25-m separation, the force on each charge will be

Accepted Answer

According to Coulomb's law, the force between two charges is inversely proportional to the square of the distance between them. Reducing the distance to 0.25 meters (one-fourth of the original distance) increases the force by a factor of (1/0.25)^2 = 16.

Question 19

The electric field around an isolated electron has a certain strength 1 cm from the electron. The electric field strength 2 cm from the electron is

Accepted Answer

The answer of The electric field around an isolated electron...

Question 20

An ampere is a unit of electrical

Accepted Answer

An ampere is a unit of electrical current, which measures the flow of electric charge.

Quiz 7: Electricity and Magnetism