Physics 2 Exam 1 Review
A charge of 2.0 µC flows onto the plates of a capacitor when it is connected to a 12. V battery. How much work was done in charging this capacitor? A) 12. µJ B) 48. µJ C) 0.14 mJ D) 21. µJ E) 24. µJ
A) 12. µJ
A force of 10 N acts on a charge of 5.0 µC when it is placed in a uniform electric field. What is the magnitude of this electric field? A) 2.0 MN/C B) 50 MN/C C) 1.0 MN/C D) 1000 MN/C E) 0.50 MN/C
A) 2.0 MN/C
The charge carried by one electron is e = -1.6 × 10-19 C. The number of excess electrons necessary to produce a charge of 1.0 C is A) 6.3 × 10^18. B) 1.6 × 10^19. C) 1.6 × 10^18. D) 6.3 × 10^9. E) 6.3 × 10^6
A) 6.3 × 10^18.
When an electron is removed from a neutral atom, it becomes A) a positive ion. B) more massive. C) a bipolar atom. D) a negative ion. E) heavier.
A) a positive ion.
Electric dipoles always consist of two charges that are A) equal in magnitude; opposite in sign. B) unequal in magnitude; opposite in sign. C) equal in magnitude; both are negative. D) equal in magnitude; both are positive
A) equal in magnitude; opposite in sign.
An equipotential surface must be A) perpendicular to the electric field at any point. B) equal to the electric field at any point. C) randomly oriented with respect to the electric field. D) parallel to the electric field at any point.
A) perpendicular to the electric field at any point.
The electric field at the surface of a conductor is A) perpendicular to the surface. B) always zero. C) never zero. D) parallel to the surface.
A) perpendicular to the surface.
The absolute potential at a distance of 2.0 m from a negative point charge is -100. V. What is the absolute potential 4.0 m away from the same point charge? A) -0.40 kV B) -50. V C) -0.20 kV D) -25. V E) -0.50 kV
B) -50. V
An electron which moves from the negative to the positive terminal of a 2.0 volt battery loses how much potential energy? A) 2.0 J B) 2.0 eV C) 4.2 × 10-19 J D) 2.0 × 10-19 J E) 3.2 J
B) 2.0 eV
The force of attraction between a -40.0 µC and +108 µC charge is 4.00 N. What is the separation between these two charges? A) 1.13 m B) 3.12 m C) 3.67 m D) 2.49 m E) 2.10 m
B) 3.12 m
A glass rod is rubbed with a piece of silk. During the process the glass rod acquires a positive charge and the silk A) acquires a positive charge also. B) acquires a negative charge. C) remains neutral. D) could either be positively charged or negatively charged. It depends on how hard the rod was rubbed.
B) acquires a negative charge.
Which of the following will increase the capacitance of a parallel plate capacitor? A) an increase in the potential difference between the plates B) an increase in the plate area and a decrease in the plate separation C) none of the above D) a decrease in the potential difference between the plates E) a decrease in the plate area and an increase in the plate separation
B) an increase in the plate area and a decrease in the plate separation
Electric Potential Energy per unit charge is called A) dielectric constant. B) potential. C) electric field. D) eV. E) power.
B) potential.
An electron and a proton are separated by a distance of 1 m. What happens to the size of the force on the proton if the electron is moved 0.5 m closer to the proton? A) It decreases to one-fourth its original value. B) It increases to 8 times its original value. C) It increases to 4 times its original value. D) It decreases to one-half its original value. E) It increases to 2 times its original value.
C) It increases to 4 times its original value.
Electric field lines A) were discovered by Franklin. B) were invented by Isaac Newton. C) are closer together the stronger the field. D) are perpendicular to the lines of force. E) start on negative charges and end on positive charges.
C) are closer together the stronger the field.
When atom A loses an electron to atom B, A) atom A becomes a negative ion and atom B becomes a positive ion. B) atom A acquires more neutrons than atom B. C) atom A becomes a positive ion and atom B becomes a negative ion. D) atom A acquires less neutrons than atom B. E) atom A becomes more negative than atom B.
C) atom A becomes a positive ion and atom B becomes a negative ion.
Electrons carry a A) neutral charge. B) positive charge. C) negative charge. D) variable charge.
C) negative charge.
The main difference between conductors and insulators is in terms of A) neutrons. B) protons. C) valence or conduction electrons. D) atoms. E) None of the other choices is correct
C) valence or conduction electrons.
A piece of plastic has a net charge of +2.00 µC. How many more protons than electrons does this piece of plastic have? A) 1.25 × 10^19 B) 2.50 × 10^13 C) 2.50 × 10^19 D) 1.25 × 10^13 E) 0
D) 1.25 × 10^13
In electricity, what quantity is analogous to the "acceleration of gravity" g (which is a force per unit mass)? A) electric charge B) electric force C) an electric dipole D) electric field E) electric potential
D) electric field
For a proton moving in the direction of the electric field A) its potential energy increases and its electric potential increases. B) its potential energy increases and its electric potential decreases. C) its potential energy decreases and its electric potential increases. D) its potential energy decreases and its electric potential decreases. E) both its potential energy and it electric potential remain constant
D) its potential energy decreases and its electric potential decreases.
Capacitors connected in series always have ________ total capacitance than any of the individual capacities. A) more B) Not enough information given. C) the same D) less
D) less
A parallel-plate capacitor has plates of area 0.20 m2 separated by a distance of 1.0 mm. What is this capacitor's capacitance? A) 22. µF B) 40. F C) 0.35 nF D) 2.0 × 102 F E) 1.8 nF
E) 1.8 nF
It takes 10. J of energy to move 2.0 C of charge from point A to point B. What is the potential difference between points A and B? A) 0.20 V B) 0.50 V C) 20. V D) zero E) 5.0 V
E) 5.0 V
A parallel-plate capacitor has plates of area 0.20 m2 separated by a distance of 1.0 mm. What is the strength of the electric field between these plates when this capacitor is connected to a 6.0 V battery? A) 3.0 kN/C B) 6.0 N/C C) 12. N/C D) 1.2 kN/C E) 6.0 N/mC
E) 6.0 N/mC
A surface on which all points are at the same potential is referred to as A) a dielectric surface. B) a constant electric field surface. C) a constant electric force surface. D) an equivoltage surface. E) an equipotential surface.
E) an equipotential surface.
A negative charge, if free, tries to move A) away from infinity. B) in the direction of the electric field. C) from high potential to low potential. D) toward infinity. E) from low potential to high potential.
E) from low potential to high potential.
Two charged objects attract each other with a certain force. If the charges on both objects are doubled with no change in separation, the force between them A) increases, but we can't say how much without knowing the distance between them. B) doubles. C) becomes zero. D) halves. E) quadruples.
E) quadruples.
A neutron carries a negative charge.
False
Negative charges, when released, accelerate toward regions of lower electric potential.
False
The capacitance of a parallel plate capacitor is directly proportional to its plate separation.
False
The coulomb, which is the unit of charge, is the charge on one electron.
False
A capacitor, in addition to storing charge, also stores electrical energy.
True
A positive charge placed in an electric field experiences a force in the direction of the field.
True
Electric charge is quantized.
True
Electric potential decreases when moving farther from positive charges or nearer to negative charges.
True
Equipotential surfaces are always at right angles to the electric field.
True
For a pair of oppositely charged parallel plates, the negatively charged plate is at a lower electric potential than the positively charged one by an amount PV .
True
The Coulomb force between two charges can be attractive or repulsive.
True
The electric field between the plates of a parallel plate capacitor is inversely proportional to the plate separation.
True
