5 Steps to a 5 500 AP Physics Questions to Know by Test Day (2012)
Chapter 12. Electrostatics
331. An object consists of subatomic particles. It has a net charge of 8.0 × 10−19 C. Which of the following statements is true?
(A) The object only has five protons.
(B) The object has no electrons.
(C) The number of protons and electrons are equal.
(D) The object has five more protons than electrons.
(E) The object has five less protons than electrons.
Questions 332 and 333 refer to the following figure:
332. An electron, proton, and neutron are fired at a uniform electric field as indicated in the figure. Which of the following statements is true?
(A) The electron will be deflected to the right, the proton will be deflected to the left, and the neutron will pass through the field.
(B) The neutron will be deflected to the right, the proton will be deflected to the left, and the electron will pass through the field.
(C) The electron will be deflected to the left, the proton will be deflected to the right, and the neutron will pass through the field.
(D) The electron will be deflected to the right, the neutron will be deflected to the left, and the proton will pass through the field.
(E) The proton will be deflected to the right, the neutron will be deflected to the left, and the electron will pass through the field.
333. If the electric field in the figure has a strength of 100 N/C, what is the magnitude and direction of the force on the electron?
(A) 1.6 × 10−21 C to the left
(B) 1.6 × 10−21 C to the right
(C) 1.6 × 10−19 C to the right
(D) 1.6 × 10−19 C to the left
(E) 1.6 × 10−17 C to the left
334. An electron is in an electric field surrounding a positive charge. It sits at an equipotential line of 20 V. What happens when it moves to another equipotential line of 40 V if the two lines are 0.5 m apart?
(A) It takes 1.6 × 10−19 J to move from 20 V to 40 V.
(B) The electron does 1.6 × 10−19 J of work moving from 20 V to 40 V.
(C) The electron does 3.2 × 10−19 J of work moving from 20 V to 40 V.
(D) It takes 3.2 × 10−19 J to move from 20 V to 40 V.
(E) It takes 8.0 × 10−20 J to move from 20 V to 40 V.
335. Two protons are 1 μm apart. What is the electric force between them?
(A) 2.3 × 10−22 N attractive
(B) 2.3 × 10−16 N attractive
(C) 0 N
(D) 2.3 × 10−16 N repulsive
(E) 2.3 × 10−22 N repulsive
336. The work done on a 1.0-μC test charge to move it from Point A to Point B in an electric field is −5.0 × 10−5 J. Which of the following statements is true?
(A) The voltage difference is 50 V, and Point B has a higher electrical potential energy (EPE) than Point A.
(B) The voltage difference is zero, and both points have the same EPE.
(C) The voltage difference is 50 V, and Point A has a higher EPE than Point B.
(D) The voltage difference is −50 V, and Point B has a higher EPE than Point A.
(E) The voltage difference is −50 V, and Point A has a higher EPE than Point B.
Questions 337–340 refer to the following figure:
337. In this figure, five negative test charges (A through E) of the same magnitude are shown at different positions in the electric field of a positive point charge (i.e., the solid lines are equipotential). Which charge has the greatest force acting on it?
(A) Test Charge A
(B) Test Charge B
(C) Test Charge C
(D) Test Charge D
(E) Test Charge E
338. In this figure, which charge has the greatest EPE?
(A) Test Charge A
(B) Test Charge B
(C) Test Charge C
(D) Test Charge D
(E) Test Charge E
339. In this figure, which charges have the same EPE?
(A) Test Charges A and B
(B) Test Charges A and C
(C) Test Charges C and D
(D) Test Charges B and E
(E) Test Charges A and E
340. Assuming that the distance between each equipotential line in this figure represents the same increment in voltage, which of the following requires the most work to be done?
(A) Moving Charge A to Charge E
(B) Moving Charge E to Charge B
(C) Moving Charge B to Charge C
(D) Moving Charge A to Charge C
(E) Moving Charge D to Charge E
341. Two charged parallel plates are spaced 1 mm apart. A voltage difference of 9 V is placed across them. What is the magnitude of the electric field between the plates?
(A) 0.009 V/m
(B) 0.09 V/m
(C) 9.0 V/m
(D) 90 V/m
(E) 9000 V/m
342. A 20-kg crate slides horizontally on a floor at 0.5 m/s and comes to rest in 25 s. What is the rate of thermal energy transferred between the crate and the floor by friction?
(A) 0.1 W
(B) 0.5 W
(C) 1.0 W
(D) 2.0 W
(E) 10 W
343. How much charge is on each plate of a 1-μF capacitor when a 12.0-V power supply is hooked up to it?
(A) 1.2 × 10−6 C
(B) 1.2 × 10−5 C
(C) 12 C
(D) 1.2 × 106 C
(E) 1.2 × 107 C
344. Two parallel plates are separated by 1 mm. The area of the plates is 1 cm2 and there is nothing but free space between the plates. What is the capacitance?
(A) 8.9 × 10−13 F
(B) 8.9 × 10−12 F
(C) 8.9 × 10−11 F
(D) 8.9 × 10−10 F
(E) 8.9 × 10−9 F
345. [For Physics C Students Only] The dotted arrows in this figure depict a uniform electric field. Five wires are depicted by the thick lines labeled A through E. The wires cut through the field. Which of the following represents the electric flux through the wires from least to greatest?
(A) A < B < C < D < E
(B) B < C < A < D < E
(C) C < E < D < A < B
(D) E < C < B < D < A
(E) C < B < D < E < A
346. A 0.1-C charge is located 3 m away from a point charge. What is the electric potential?
(A) 1 × 10−9 V
(B) 3 × 10−9 V
(C) 3 × 108 V
(D) 1.0 × 108 V
(E) 1 × 109 V
347. A 0.2-C charge is in an electric field. It feels like a force of 100 N. What is the strength of the electric field?
(A) 5.0 N/C
(B) 20 N/C
(C) 50 N/C
(D) 200 N/C
(E) 500 N/C
348. A negatively charged object is placed against a neutral object and becomes attracted to one side. Which of the following is true?
(A) The neutral object gains positive charges to become positively charged.
(B) The neutral object loses negative charges to become positively charged.
(C) The neutral object loses positive charges to become negatively charged.
(D) The neutral object gains negative charges to become negatively charged.
(E) Negative charges of the neutral object move to the side opposite the negatively charged object.
349. When placed in a uniform electric field directed to the right, which of the following will move to the right?
(A) Electron
(B) Neutron
(C) Proton
(D) Antiproton
(E) Hydrogen atom
350. When a 0.05-C charge is placed in a field and experiences 100 J of potential energy, what is the voltage?
(A) 5.0 V
(B) 200 V
(C) 500 V
(D) 2,000 V
(E) 20,000 V
351. A test charge is located 10 m away from a point charge in a uniform electric field of 900 N/C. What is the magnitude of the test charge?
(A) 1 μC
(B) 10 μC
(C) 100 μC
(D) 1 mC
(E) 10 mC
352. Two parallel plates have a 120-V potential difference across them and produce a uniform electric field of 1.2 × 106 V/m. How far apart are the plates?
(A) 1 μm
(B) 0.1 mm
(C) 1 mm
(D) 10 mm
(E) 1 cm
353. A 100-μF capacitor is charged by a 1.5-V battery. How much charge is stored on each plate?
(A) 1.5 × 10−6 C
(B) 1.5 × 10−4 C
(C) 0.15 C
(D) 67 C
(E) 150 C
354. What strength and direction of an electric field is necessary to suspend a proton against the force of gravity?
(A) 1 × 106 N/C downward
(B) 1 × 107 N/C upward
(C) 1 × 107 N/C downward
(D) 6 × 107 N/C upward
(E) 6 × 1019 N/C upward
355. A 1-μF capacitor has plates that are 0.2 mm apart. There is only empty space between the plates. What is the area of the plates?
(A) 0.22 m2
(B) 2.2 m2
(C) 22 m2
(D) 220 m2
(E) 2,200 m2
356. In this figure, a beam of particles is shot through two electric fields at a target. Both electric fields are uniform and directions are indicated by the arrows. Which of the following particles will reach the target?
(A) Electrons
(B) Protons
(C) Positrons
(D) Neutrons
(E) Alpha particles
357. A 1-g object with a charge of −0.5 C is at rest. A uniform electric field of 10 N/C is applied to it. The field is oriented to the right. What will be the acceleration of the object in the field?
(A) 50 m/s2 to the left
(B) 50 m/s2 to the right
(C) 500 m/s2 to the right
(D) 500 m/s2 to the left
(E) 5,000 m/s2 to the left
358. An electron in an electric field experiences a force of 1 × 106 N opposite the direction of the field. What is the magnitude of the electric field?
(A) 1.7 × 10−25 N/C
(B) 1.7 × 10−24 N/C
(C) 5.9 × 1024 N/C
(D) 5.9 × 1025 N/C
(E) 1.7 × 1026 N/C
359. A proton is initially at rest. A uniform electric field is applied across it by two plates that are 1 m apart. The plates are charged by a 1.5-V battery. The electric field is applied for 1 μs to accelerate the proton uniformly.
(a) What is the strength of the electric field?
(b) What is the force on the proton while the electric field is applied?
(c) What is the acceleration of the proton?
(d) What will be the final velocity of the proton when the field is turned off?
(e) How far will the proton travel during the time that the electric field is applied?
360. Three electrons (A, B, C) are located at 2 nm, 4 nm, and 16 nm, respectively, away from a proton.
(a) What are the magnitudes of the electric fields experienced by each electron? Which one experiences the greatest field?
(b) What are the voltages experienced by each electron? Which one experiences the lowest voltage?
(c) What are the forces experienced by each electron? Which one experiences the greatest force?