Electrostatics ReviewElectrostatics Review

LCHS

Dr.E

Which is a vector quantity?

(A) speed(B) work (C) mass(D) displacement

Which object has the greatest inertia?

(A) a 5.00-kg mass moving at 10.0 m/s(B) a 10.0-kg mass moving at 1.00 m/s(C) a 15.0-kg mass moving at 10.0 m/s(D) a 20.0-kg mass moving at 1.00 m/s

A positive test charge is placed between an electron, e, and a proton, p, as shown in the diagram below.

When the test charge is released, it will move toward

(A) A (B) B (C) C (D) D

In an electric field, 0.90 joule of work is required to bring 0.45 coulomb of charge from point A to point B. What is the electric potential difference between points A and B?

(A) 5.0 V (B) 2.0 V(C) 0.50 V(D) 0.41 V

In the diagram above, proton p, neutron n, and electron e are located as shown between two oppositely charged plates. The magnitude of acceleration will be greatest for the

(A) neutron, because it has the greatest mass (B) neutron, because it is neutral (C) electron, because it has the smallest mass (D) proton, because it is farthest from negative plate

Two protons are located one meter apart. Compared to the gravitational force of attraction between the two protons, the electrostatic force between the protons is

(A) stronger and repulsive (B) weaker and repulsive (C) stronger and attractive (D) weaker and attractive

A balloon is rubbed against a student’s hair and then touched to a wall. The balloon “sticks” to the wall due to

(A) electrostatic forces between the particles of the balloon(B) magnetic forces between the particles of the wall(C) electrostatic forces between the particles of the balloon and the particles of the wall (D) magnetic forces between the particles of the balloon and the particles of the wall

Two positively charged masses are separated by a distance, r. Which statement best describes the gravitational and electrostatic forces between the two masses?

(A) Both forces are attractive. (B) Both forces are repulsive. (C) The gravitational force is repulsive and the

electrostatic force is attractive. (D) The gravitational force is attractive and the electrostatic force is repulsive.

A distance of 1.0 meter separates the centers of two small charged spheres. The spheres exert gravitational force Fg and electrostatic force Fe oneach other. If the distance between the spheres’ centers is increased to 3.0 meters, the gravitational force and electrostatic force, respectively, may be represented as

(A) Fg and Fe (B) 3Fg and 3Fe

9 9

(C) Fg and Fe (D) 9Fg and 9Fe

3 3

A beam of electrons is directed into the electric field between two oppositely charged parallel plates. The electrostatic force exerted on the electrons by the electric field is directed

(A) into the screen (B) out of the screen (C) toward the bottom of the screen (D) toward the top of the screen

The particles in a nucleus primarily by the are held together

(A) magnetic force(B) gravitational force(C) electrostatic force (D) strong force

A charge of 30 coulombs passes through a 24-ohm resistor in 6.0 seconds. What is the current through the resistor?

(A) 1.3 A (B) 5.0 A(C) 7.5 A(D) 4.0 A

The diagram represents the electric field surrounding two charged spheres, A and B. What is the sign of the charge of each sphere?

(A) Sphere A is positive and sphere B is negative.(B) Sphere A is negative and sphere B is positive.(C) Both spheres are positive.(D) Both spheres are negative.

The centers of two small charged particles are separated by a distance of 1.2 × 10–4 meter. The charges on the

particles are +8.0 × 10–19 Coulomb and +4.8 × 10–19 Coulomb, respectively.

Calculate the magnitude of the electrostatic force between these two

particles.

A potential difference of 10.0 volts exists between two points, A and B, within an electric field. What is the magnitude of charge that requires 2.0 10–2 joule of work to move it from A to B?

(A) 5.0102 C(B) 2.010–1 C(C) 5.010–2 C (D) 2.010–3 C

Two small identical metal spheres, A and B, on insulated stands, are each given a charge of 2.0 10–6 Coulomb. The

distance between the spheres is 2.0 10–1 meter.

Calculate the magnitude of the electrostatic force that the charge on

sphere A exerts on the charge on sphere B.

The diagram below represents an electron within an electric field between two parallel plates that are charged with a potential difference of 40.0 volts. If the magnitude of the electric force on the electron is 2.00 10–15 newton, the magnitude of the electric field strength between the charged plates is(A) 3.20 10–34 N/C (B) 2.00 10–14 N/C(C) 1.25 104 N/C (D) 2.00 1016 N/C

Two small metallic spheres, A and B, are separated by a distance of 4.0 10–1 meter, as shown. The charge on each sphere is 1.0 10–6 coulomb. Point P is located near the spheres. What is the magnitude of the electrostatic force between the two charged spheres?(A) 2.210–2 N (B) 5.6x10–2 N(C) 2.2104 N (D) 5.6104 N

An electroscope is a device with a metal knob, a metal stem, and freely hanging metal leaves used to detect charges. The diagram shows a positively charged leaf electroscope. As a positively charged glass rod is brought near the knob of the electroscope, the separation of the electroscope leaves will (A) decrease (B) increase (C) remain the same

Compared to insulators, metals are better conductors of electricity because metals contain more free (A) protons (B) positive ions (C) electrons (D) negative ions

Electrostatic force F exists between two point charges. If the distance between the charges is tripled, the force between the charges will be

(A) F/9 (B) 3F (C) F/3 (D) 9F

How much work is done in moving 5.0 coulombs of charge against a potential difference of 12 volts?

(A) 2.4 J (B) 30. J (C) 12 J (D) 60. J

How much work is required to move a single electron through a potential difference of 100. volts?

(1) 1.6 × 10–21 J (3) 1.6 × 10–17 J (2) 1.6 × 10–19 J (4) 1.0 × 102 J

Metal sphere A has a charge of +12 elementary charges and identical sphere B has a charge of +16 elementary charges. After the two spheres are brought into contact, the charge on sphere A is

(A) –2 elementary charges (B) +2 elementary charges (C) +14 elementary charges (D) +28 elementary charges

What is the approximate electrostatic force between two protons separated by a distance of 1.0 10⋅ –6 meter?

(1) 2.3 10⋅ –16 N and repulsive (2) 2.3 10⋅ –16 N and attractive (3) 9.0 10⋅ 21 N and repulsive (4) 9.0 10⋅ 21 N and attractive