Students have four identical, hollow, uncharged conducting spheres, W, X, Y, and Z. The separate spheres are given the charges shown in the figure and held at the corners of a square. Which of the following relationships between electric forces can be explained with the concept of action-reaction pairs of forces?

The force that sphere Y exerts on sphere X has the same magnitude as the force that sphere X exerts on sphere Y.

The force that sphere W exerts on sphere X has the same magnitude as the force that sphere Y exerts on sphere X.

The force that sphere Y exerts on sphere X has the same magnitude as the force that sphere Y exerts on sphere Z.

The force that sphere W exerts on sphere Y has the same magnitude as the force that sphere Z exerts on sphere X.

Which of the following statements is true of gravitational force but cannot describe electric force?

The influence of gravitational force dominates over extremely large scales in the universe.

The magnitude of gravitational force is inversely proportional to the square of the distance between objects.

Gravitational force can be both attractive and repulsive.

The influence of gravitational force dominates over extremely large scales in the universe.

A student observes that two identical, charged pith balls hanging on insulating strings repel each other and reach equilibrium an angle θ from the vertical. A student claims that the angle θ will always be less than 90 0 . Based on this claim, which of the following reasoning statements is correct?

The tension force in each string must have a vertical component that is equal and opposite to the gravitational force exerted on the pith ball by Earth.

The tension force in each string must have a horizontal component that is equal and opposite to the electrostatic force exerted between the pith balls.

The tension force in each string must have a horizontal component that is equal and opposite to the vector sum of the electrostatic force acting on the pith balls.

The tension force in each string must have a vertical component that is equal and opposite to the vector sum of the gravitational force acting on the pith balls.

A student has two balloons attached to strings and rubs each balloon on one of two different materials. The student wants to know whether or not the balloons have the same sign charge. Which of the following procedures will provide enough information while ensuring the net charge on the balloons is not affected? Select two answers.

Suspending the balloons near each other and observing which way they deflect

Suspending each balloon near the material it was not rubbed on and seeing which way it deflects

Touching the balloons to each other and observing whether they stick together

Touching each balloon to the material it was not rubbed on and observing whether they stick together

Solid metal cube A is initially charged and identical cube B is initially uncharged, as shown in the left figure. The cubes are then brought together as shown in the right figure. Which of the following best describes the charge on the cubes when they are in contact

Both cubes have the same net charge that is distributed on all of their surfaces except the ones in contact.

Both cubes have the same net charge that is distributed throughout their volumes

Both cubes have the same net charge that is distributed on all of their surfaces.

Both cubes have a net charge that is distributed on all of their surfaces except the ones in contact, but cube A has more charge than cube B.

A student has a balloon that looks shiny like a metal and wants to perform an experiment to determine if it contains any metal. Which of the following procedures could possibly determine if the balloon contains metal?

Hold a positively charged rod near the uncharged balloon, then hold a negatively charged rod near the uncharged balloon, and observe whether the balloon is attracted or repelled by the rods.

Charge the balloon, hold it near an electroscope, and determine if the electroscope leaves move.

Hold a positively charged rod near the uncharged balloon, then hold a negatively charged rod near the uncharged balloon, and observe whether the balloon acquires a net charge.

Four charged particles, A , B , C, and D , are fixed in place in the arrangement shown in the figure. Particle BB has a charge of +q , while particles C and D have charges of −q . The net force on BB exerted by the other three charges is zero. Which of the following is a Newton’s third law pair of forces for this situation?

The force that particle A exerts on particle B and the force that particle B exerts on particle A

The force that particle A exerts on particle C and the force that particle A exerts on particle D

The force that particle B exerts on particle A and the force that particle B exerts on particle C

A student is designing an experiment to determine which materials are better for observing electrostatic induction. The student charges different materials, then brings each object near a charged electroscope, as shown in the figure, and records what the leaves of the electroscope do, as shown in the table. What claims can the student make from the results? Select two answers.

The glass rod has a charge of opposite sign to that of the other objects.

The glass rod’s charge has the opposite sign as that of the electroscope’s charge.

All four objects have charges of the same magnitude.

The electroscope leaves only move if the object is charged negatively.

The diagram shows a positively charged particle with an electric force F to the right exerted on it. A, B, C, and D indicate points at which positive or negative point charges may be placed. Which of the following could form a Newton’s-third-law pair with the force F? Select two answers

The force the particle exerts on a positive charge at point A

The force exerted on the particle by a negative charge at point C

The force exerted on the particle by a positive charge at point B

The force the particle exerts on a negative charge at point D

The figure shows an electroscope. A conducting sphere is connected by a vertical metal bar to the leaves, which are thin, light strips of conducting material. The electroscope initially is neutral, so the leaves are hanging together. A charged rod is touched to the sphere and then removed, which results in the leaves separating. As a positively charged object is then brought near the sphere of the electroscope, which of the following observed results and explanations correctly identify the sign of the charged rod? Select two answers.

The leaves move farther apart, so the charged rod is therefore positive.

The leaves come closer together, so the charged rod is therefore negative.

The leaves come closer together, so the charged rod is therefore positive.

The leaves move farther apart, so the charged rod is therefore negative

A student created the following procedure to rearrange the charges within an uncharged conducting rod so that one end of the rod is positive and the other end is negative. Step 1: Give a conducting sphere a net positive charge. Step 2: Touch the positive sphere to one end of the conducting rod. Step 3: Remove the sphere far from the conducting rod. The student finds that his procedure does not work. Which of the following modifications to one of the steps, if any, will allow the procedure to accomplish the goal of having one end of the rod be positive and the other end be negative?

None of these steps will by itself allow the procedure to work as intended.

In Step 1, the sphere should be given a negative charge.

In Step 2, the sphere should be brought near, but should not touch, the conducting rod.

In Step 3, the sphere should not be removed from contact with the conducting rod.

Two identical blocks each have a mass of 1.00kg and a net charge of +1.00μC each. Which of the following statements is true regarding the relative magnitudes of the electric and gravitational force each block exerts on the other?

The magnitude of the electric force is much larger than the magnitude of the gravitational force

The two forces are of similar magnitude.

The magnitude of the gravitational force is much larger than the magnitude of the electric force

The relative magnitudes of the two forces cannot be determined without knowing the distance between the blocks

QUIZ: Coloumb's Law and Charges

Quiz

•

Physics

•

10th Grade

•

Practice Problem

•

Hard

Roxan Choudhry

Used 10+ times

FREE Resource

26 questions

Show all answers

MULTIPLE CHOICE QUESTION

1 min • 1 pt

Which of the following provides evidence that there must be at least two types of electrical charge, but that there is only one type of mass?

The magnitude of the Coulomb's law constant differs greatly from the magnitude of the universal gravitational constant.

Contact forces such as friction are caused primarily by electrostatic forces and not by gravitational ones.

The electric force has a relative strength that is much greater than the strength of the gravitational force.

On the scale of the solar system, electric forces cancel out and gravitational forces dominate.

MULTIPLE CHOICE QUESTION

1 min • 1 pt

Two small conducting spheres hang from insulating strings and are in contact, as shown in Figure 1. A positively charged rod then touches the left sphere and the two spheres repel, as shown in Figure 2. Which of the following correctly identifies the charges on the left and right spheres as the two spheres hang as shown in Figure 2?

MULTIPLE CHOICE QUESTION

1 min • 1 pt

Two pieces of electrically neutral tape are stuck together. The sticky side of the top piece is stuck to the back side of the bottom piece, as shown in the diagram. A student pulls them apart quickly. Afterward, the student holds the backs (nonsticky sides) of the two pieces of tape near one another, and they attract. The attraction of the pieces is evidence of which of the following?

The two pieces of tape have equal amounts of excess charge.

There are two types of charge, and these two types attract each other.

The charge on the top piece is negative, and the charge on the bottom piece is positive.

The charge on the pieces is due to the electrons moving from one piece to the other.

MULTIPLE CHOICE QUESTION

1 min • 1 pt

The figure shows two identical, initially uncharged conducting spheres. Sphere B is grounded and sphere A is not grounded. A positively charged rod is brought close to but does not touch sphere A, as shown. The rod is then removed. A student claims that both spheres are now charged. Is the student correct? Why or why not?

Yes. When the rod is brought near, both spheres become negatively charged

Yes. The ground on sphere B ensures that there is no movement of charge on either sphere when the rod is removed.

No. When the rod is brought near, sphere A is polarized and sphere B gains a net negative charge. When the rod is removed, sphere B remains charged but sphere A does not remain polarized.

No. When the rod is removed, the situation is identical to before the rod was brought near, so both spheres are uncharged.