Practice Quiz (Ch 22)
1) The fundamental force underlying all chemical reactions is
A) gravitational.
B) nuclear.
C) centripetal.
D) electrical.
E) None of the above choices are correct.
Answer: D
2) A positive ion has more
A) electrons than neutrons.
B) electrons than protons.
C) protons than electrons.
D) protons than neutrons.
E) neutrons than protons.
Answer: C
3) To say that electric charge is quantized is to say that the charge on an object
A) may occur in an infinite variety of quantities.
B) is a whole-number multiple of the charge of one electron.
C) will interact with neighboring electric charges.
D) can be neither created nor destroyed.
E) is sometimes positive.
Answer: B
4) The unit of electric charge, the coulomb, is the charge on
A) one electron.
B) a specific large number of electrons.
C) a neutron.
D) a specific number of neutrons.
E) a quark.
Answer: B
5) The electrical force between charges is strongest when the charges are
A) close together.
B) far apart.
C) The electric force is constant everywhere.
Answer: A
6) A transistor is an example of a
A) resistor.
B) superconductor.
C) semiconductor.
D) dry cell.
E) transmitter.
Answer: C
7) Rub electrons from your hair with a comb and the comb becomes
A) negatively charged.
B) positively charged.
C) discharged.
Answer: A
8) Two protons attract each other gravitationally and repel each other electrically. By far the
greater force is
A) the gravitational attraction.
B) the electrical repulsion.
C) neither – the forces are the same.
Answer: B
9) To say that an object is electrically polarized is to say
A) it is electrically charged.
B) its charges have been rearranged.
C) its internal electric field is zero.
D) it is only partially conducting.
E) it is to some degree magnetic.
Answer: B
10) When a car is struck by lightning, the resulting electric field inside the car is
A) normally huge, but for a brief time.
B) normally huge for a time longer than the lightning stroke itself.
C) small enough to be safe for an occupant inside.
D) zero.
Answer: D
11) The electric field inside the dome of a Van de Graaff generator
A) depends on the amount of charge the outside of dome.
B) depends on the volume of the dome
C) Choices A and B are both correct.
D) None of the above choices are correct.
Answer: D
12) The net charge on a charged capacitor depends on
A) the area of the capacitor plates.
B) the distance between the capacitor plates.
C) the medium between the capacitor plates.
D) All of the above choices are correct.
E) None of the above choices are correct – the net charge is zero.
Answer: E
13) When the distance between two charges is halved, the electrical force between the charges
A) quadruples.
B) doubles.
C) halves.
D) is reduced by 1/4.
E) None of the above choices are correct.
Answer: A
14) If you comb your hair and the comb becomes positively charged, then your hair becomes
A) positively charged.
B) negatively charged.
C) uncharged.
Answer: B
15) A difference between electric forces and gravitational forces is that gravitational forces are
not affected by
A) separation distance.
B) repulsive interaction.
C) the inverse-square law.
D) infinite range.
E) None of the above choices are correct.
Answer: B
16) A negatively charged rod is held near a metal can that rests on a dry wood table. If you touch
the opposite side of the can momentarily with your finger, the can is then
A) positively charged.
B) negatively charged.
C) partially discharged.
D) completely discharged.
E) discharged only on the side touched.
Answer: A
17) The direction of an electric field is the direction of the force that the field would exert on
A) a neutral test charge.
B) an electron.
C) an atom.
D) a proton.
E) a molecule.
Answer: D
18) 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
A) less than 10 V.
B) 10 V.
C) more then 10 V.
D) None of the above choices are correct.
Answer: B
19) 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
A) fall closer together.
B) spread apart further.
C) do not move.
Answer: A
20) In the unlikely case of a lightning strike, it is worse to be inside a building framed with
A) steel.
B) iron.
C) aluminum.
D) wood.
Answer: D
21) A proton and an electron are placed in an electric field. Which undergoes the greater
acceleration?
A) electron
B) proton
C) Both accelerate equally.
D) Neither accelerates.
Answer: A
22) Two charges separated by one meter exert 1-N forces on each other. If the charges are
pushed to 1/4 meter separation, the force on each charge will be
A) 1 N.
B) 2 N.
C) 4 N.
D) 8 N.
E) 16 N.
Answer: E
23) Two charges separated by one meter exert 1-N forces on each other. If the magnitude of each
charge is doubled, the force on each charge is
A) 1 N.
B) 2 N.
C) 4 N.
D) 8 N.
E) None of the above choices are correct.
Answer: C
24) Two charged particles repel each other with a force F. If the charge of one of the particles is
doubled and the distance between them is also doubled, then the force will be
A) F.
B) 2 F.
C) F/2.
D) F/4.
E) none of these
Answer: C
25) When a single charge q is placed on one corner of a square, the electric field at the center of
the square is F/q. If three other equal charges are placed on the other corners, the electric field at
the center of the square due to these four equal charges is
A) F/q.
B) 4F/q.
C) F/(2q).
D) F/(4q).
E) None of the above choices are correct.
Answer: E
26) 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
A) 0.25 V.
B) 0.5 V.
C) 1 V.
D) 2 V.
E) 4 V.
Answer: C
27) Two charged particles held close to each other are released. As they move, the force on each
particle increases. Therefore, the particles must have
A) the same sign.
B) opposite signs.
C) the same mass.
D) the same size.
E) impossible to answer without additional information
Answer: B
28) A positive charge and a negative charge held near each other are released. As they move, the
force on each particle
A) increases.
B) decreases.
C) stays the same.
Answer: A