61. Which statements are correct?
· An equipotential surface is one on which all points are at the same electric potential. Equipotential surfaces are perpendicular to electric field lines.
o An equipotential surface is one on which all points are at the same electric potential. Equipotential surfaces are parallel to electric field lines.
o An equipotential surface is one on which all points are not at the same electric potential. Equipotential surfaces are perpendicular to electric field lines.
o An equipotential surface is one on which all points are at the same electric potential. Equipotential surfaces are perpendicular to gravitation field lines.
o No correct answer
62. If we define V = 0 at rA = ∞ the electric potential due to a point charge at any distance r from the charge is:
· 
o 
o 
o 
o No correct answer
63. The potential energy associated with a pair of point charges separated by a distance r 12 is:
· 
o 
o 
o 
o No correct answer
64. The electric potential due to a continuous charge distribution is:
· 
o 
o 
o 
o No correct answer
65. The capacitance C of any capacitor is the ratio of the charge Q on either conductor to the potential difference ∆ V between them:
· 
o 
o 
o 
o No correct answer
66. The SI unit of capacitance is:
· C/V
o V/C
o C/V2
o C/V·m
o No correct answer
67. The equivalent capacitance of a parallel combination of capacitors is:
· Ceq=C1+C2+C3+...
o 1/Ceq=1/C1+1/C2+1/C3+...
o Ceq=C1=C2=C3=...
o Ceq=C1·C2·C3·...
o No correct answer
68. If two or more capacitors are connected in series, the equivalent capacitance of the series combination is given by:
o Ceq=C1+C2+C3+...
· 1/Ceq=1/C1+1/C2+1/C3+...
o Ceq=C1=C2=C3=...
o Ceq=C1·C2·C3·...
o No correct answer
69. The energy stored in a capacitor with charge Q is:
· 
o 
o 
o 
o No correct answer
70. The electric dipole moment p of an electric dipole has a magnitude:
· p=2aQ
o p=Q
o p=Q2
o p=-2aQ
o No correct answer
71. The torque acting on an electric dipole in a uniform electric field E is:
· τ = p x E
o τ = p · E
o τ = p / E
o τ =q p x E
o No correct answer
72. The potential energy of the system of an electric dipole in a uniform external electric field E is:
· U=- p · E
o U= p x E
o U= p · E
o No correct answer
o U= p / E
73. he electric current I in a conductor is defined as:
· 
o 
o 
o 
o No correct answer
74. The average current in a conductor is related to the motion of the charge carriers through the relationship:
· Iav=nqvdA
o Iav=nqvd
o Iav=qvdA
o Iav=nq/vdA
o No correct answer
75. The magnitude of the current density J in a conductor is:
· J=I/A
o J=IA
o J=IA2
o J=I2/A
o No correct answer
76. Ohm’s law in the differential form is:
· J =σ E
o I=U/R
o I=R/U
o J =σ/ E
o No correct answer
77. Ohm’s law in the integral form is:
o J =σ E
· I=U/R
o I=R/U
o J =σ/ E
o No correct answer
78. The resistance R of a conductor is defined as:
· R=∆V/I
o R =σ E
o R=∆V·I
o R=I/∆V
o No correct answer
79. For a uniform block of material of cross sectional area A and length l, the resistance over the length l is:
· 
o 
o 
o 
o No correct answer
80. The power supplied to the element, is:
· P=I∆V
o P=I/∆V
o P=I2∆V
o P=I∆V2
o No correct answer
81. The power delivered to a resistor can be defined as:
· P=I2R
o P=IR
o P=IR2
o P=I2/R
o No correct answer
82. The equivalent resistance of a set of resistors connected in series is:
· Req=R1+R2+R3+...
o 1/Req=1/R1+1/R2+1/R3+...
o Req=1/(R1+R2+R3+...)
o Req=R1+R2+R3+...
o No correct answer
83. The equivalent resistance of a set of resistors connected in parallel is found from the relationship:
o Req=R1+R2+R3+...
· 1/Req=1/R1+1/R2+1/R3+...
o Req=1/(R1+R2+R3+...)
o Req=R1+R2+R3+...
o No correct answer
84. Circuits involving more than one loop are conveniently analyzed with the use of Kirchhoff’s rules:
· 1. The sum of the currents entering any junction in an electric circuit must equal the sum of the currents leaving that junction. 2. The sum of the potential differences across all elements around any circuit loop must be zero.
o 1. The product of the currents entering any junction in an electric circuit must equal the sum of the currents leaving that junction. 2. The sum of the potential differences across all elements around any circuit loop must be constant.
o 1. The sum of the currents at any circuit loop must be zero. 2. The sum of the potential differences across all elements around any circuit loop must be zero.
o 1. The sum of the currents entering any junction in an electric circuit must equal the sum of the currents leaving that junction. 2. The product of the potential differences across all elements around any circuit loop must be zero.
o No correct answer
85. Two objects, with different sizes, masses, and temperatures, are placed in thermal contact. Energy travels
o From the larger object to the smaller object,
o From the object with more mass to the one with less,
· From the object at higher temperature to the object at lower temperature,
o Energy doesn’t travel,
o From the object at lower temperature to the object at higher temperature,
86. On a day when the temperature reaches 50°F, what is the temperature in degrees Celsius and in kelvins?
o 500 C, 323 K,
o 400 C, 313 K,
o 300 C, 303 K,
o 200 C, 293 K,
· 100 C, 283 K.
87. A helium-filled rubber balloon is left in a car on a cold winter night. Compared to its size when it was in the warm car the afternoon before, the size the next morning is
o Larger
· Smaller
o Unchanged
88. The first law of thermodynamics can be given as ________.
o for any spontaneous process, the entropy of the universe increases
o the entropy of a pure crystalline substance at absolute zero is zero
o ΔS = Q/T at constant temperature
· ΔE = Q + W
89. The second law of thermodynamics can be given as __________
· for any spontaneous process, the entropy of the universe increases
o the entropy of a pure crystalline substance at absolute zero is zero
o ΔS = Q/T at constant temperature
o ΔE = Q + W
90. Which of the following is not a state function?
o Pressure
o Volume
o Temperature
· Mole
91. Two containers hold an ideal gas at the same temperature and pressure. Both containers hold the same type of gas but container B has twice the volume of container A. The average translational kinetic energy per molecule in container B is
o twice that for container A
· the same as that for container A
o half that for container A
o impossible to determine.
92. Two containers hold an ideal gas at the same temperature and pressure. Both containers hold the same type of gas but container B has twice the volume of container A. The internal energy of the gas in container B is
· twice that for container A
o the same as that for container A
o half that for container A
o impossible to determine
93. Two containers hold an ideal gas at the same temperature and pressure. Both containers hold the same type of gas but container B has twice the volume of container A. The rms speed of the gas molecules in container B is
o twice that for container A
· the same as that for container A
o half that for container A
o impossible to determine
94. 
How does the internal energy of an ideal gas change as it follows path 
in figure?
· 
increases
o decreases
o stays the same
o There is not enough information to determine how changes
95. 
How does the internal energy of an ideal gas as it follows path 
along the isotherm labeled 
in figure?
o increases
o decreases
· stays the same
o There is not enough information to determine how changes
96. Latent heat is
· the heat released or absorbed by a thermodynamic system during a process that occurs without a change in temperature
o the amount of energy needed to raise the temperature of sample by 1°C
o the heat capacity per unit mass
o the amount of heat required to change a unit mass of a substance by one degree in temperature
o amount of energy necessary to raise the temperature of 1 g of water from 14.5°C to 15.5°C.
97. Adiabatic process is
o process that occurs at constant volume
o process that occurs at constant temperature
o process that occurs at constant pressure
· process in which the net heat transfer between the system and its surroundings is zero
o process that obeys the relation: pVn=C
98. A diatomic gas molecule has... degrees of freedom
o 3
o 5
· 6
o 7
o 7 and more
99. Energy may be transferred by
o work
o conduction
o convection
o radiation
· all answers are correct
100. The molar specific heat of a gas is measured at constant volume and found to be 11 R /2. The gas is most likely to be
o monatomic
o diatomic
o monatomic or diatomic, depends on the conditions
· polyatomic
o all answers are incorrect
101. Parallel wires carrying currents I1 and I2 respectively
· repel if they are directed opposite
o will attract if they are directed opposite
o will not interact
102. What are the opposite ends of a magnet called?
o Its terminals
· Its north and south poles
o Its magnetic fields
o Its electromagnetic poles
103. How are electrical charges and magnetic poles similar?
· Unlike attract and the same type repel
o Both are plus and minus
o Magnetic poles attract electrons
o Both change positive to negative charges
104. How can you show that electricity creates a magnetic field?
· Use a compass near a wire with current flowing through it
o Only magnets create magnetic fields
o Move a wire through a magnetic field
o Connect a battery to the magnetic field
105. How can you make an electromagnet?
o Attach a natural magnet to a battery
· Run current through a wire wrapped around an iron rod
o Line up the N and S poles of a magnet with an electric wire
o Wrap a magnet around a piece of wire with current flowing through it
106. What happens when you turn off the current in an electromagnet?
· The magnetism is turned off
o The current keeps flowing because of the magnetic force
o The electromagnet reverses its polarity
o The electromagnet becomes a generator
107. How can you create electricity with a magnet?
o Attach a magnet to a battery
o By putting a current through a wire around a magnet
· By moving a wire through a magnetic field
o You can't, because only friction on electric charges creates electricity
108. Can you create electricity with a magnet?
o No, because only friction on electric charges or batteries create electricity
· Yes, by moving a wire through a magnetic field
o Yes, by putting a current through a wire around a magnet
o Yes because magnets use electricity to stay effective
109. The geomagnetic field
o makes the Earth like a huge horseshoe magnet
o runs exactly through the geographic poles
· makes a compass work
o makes an electromagnet work
110. A material that can be permanently magnetized is generally said to be
o magnetic
o electromagnetic
o permanently magnetic
· ferromagnetic
111. The magnetic flux around a straight current-carrying wire
o gets stronger with increasing distance from the wire
· is strongest near the wire
o does not vary in strength with distance from the wire
o consists of straight lines parallel to the wire
112. The gauss is a unit of
o overall magnetic field strength
o ampere-turns
· magnetic flux density
o magnetic power
113. If a wire coil has 10 turns and carries 500 mA of current, what is the magnetomotive force in ampere-turns?
o 5,000
o 50
· 5.0
o 0.02
114. Which of the following is not generally observed in a geomagnetic storm?
o Charged particles streaming out from the Sun
o Fluctuations in the Earth’s magnetic field
o Disruption of electrical power transmission
· Disruption of microwave propagation
115. A device that reverses magnetic field polarity to keep a dc motor rotating is
o a solenoid
o an armature coil
· a commutator
o a field coil
116. When the speed at which a conductor is moved through a magnetic field is increased, the induced voltage
· increases
o decreases
o remains constant
o reaches zero
117. The induced voltage across a coil with 250 turns that is located in a magnetic field that is changing at a rate of 8 Wb/s is
o 1,000 V
· 2,000 V
o 31.25 V
o 3.125 V
118. For a given wirewound core, an increase in current through the coil
o reverses the flux lines
o decreases the flux density
· increases the flux density
o causes no change in flux density
119. If the cross-sectional area of a magnetic field increases, but the flux remains the same, the flux density
o Increases
· decreases
o remains the same
o doubles
120. When the current through the coil of an electromagnet reverses,
· direction of the magnetic field reverses
o direction of the magnetic field remains unchanged
o magnetic field expands
o magnetic field collapses
121. What is the reluctance of a material that has a length of 0.07 m, a cross-sectional area of 0.014 m2, and a permeability of 4,500 
Wb/At Ч m?
· 1111 At/Wb
o 111 At/Wb
o 11 At/Wb
o 1 At/Wb
122. A coil of wire is placed in a changing magnetic field. If the number of turns in the coil is decreased, the voltage induced across the coil will
o increase
· decrease
o remain constant
o be excessive
123. What is the flux density when the flux is 5.5 Wb and the cross-sectional area is 6 Ч 10–3 m2?
o 91.7 µT
· 917 µT
o 91 T
o 9.7 T
124. If the steel disk in a crankshaft position sensor has stopped with the tab in the magnet's air gap, the induced voltage
o increases
o decreases
· is zero
o will remain constant
125. What is the flux density in a magnetic field in which the flux in 0.1 m2 is 600 Wb?
· 6,000 µT
o 600 µT
o 600 T
o 6 T
126. The Coulomb’s law ia an equation giving the magnitude of the electric force (sometimes called the Coulomb force) between two point charges:
· 
o 
o 
o 
o No correct answer
127. The SI units for Coulomb constant ke are:
· N·m2/C2
o N·m/C
o N·m/C2
o m2/C2
o No correct answer
128. The electric field vector E can be expressed as:
· E = F e/q
o E = F e/q2
o E = F e·q
o E = F e·q2
o No correct answer
129. Which statements are correct?
· Charges of opposite sign attract one another and charges of the same sign repel one another. Total charge in an isolated system is conserved. Charge is quantized.
o Charges of opposite sign repel one another and charges of the same sign attract one another. Total charge in an isolated system is conserved. Charge is quantized.
o Charges of opposite sign attract one another and charges of the same sign repel one another. Total charge in an isolated system is not conserved. Charge is quantized.
o Charges of opposite sign repel one another and charges of the same sign attract one another. Total charge in an isolated system is ot conserved. Charge is not quantized.
o No correct answer
130. Which statements are correct?
· Conductors are materials in which electrons move freely. Insulators are materials in which electrons do not move freely.
o Insulators are materials in which electrons move freely. Conductors are materials in which electrons do not move freely.
o Conductors are materials in which electrons don’t move freely. Insulators are materials in which electrons move freely.
o All answers are correct
o No correct answer
131. If the electric field is uniform and makes an angle θ with the normal to a surface of area A, the electric flux through the surface is:
· ΦE = EA cos θ
o ΦE = EA sin θ
o ΦE = A cos θ sin θ
o ΦE = E cos θ
o No correct answer
39.
A. +
B.
C.
D.
132. Gauss’s law says that the net electric flux ΦE through any closed gaussian surface is equal to:
· ΦE=qin/ε0
o ΦE=qin·ε0
o ΦE= ε0/qin
o ΦE=qinqout/ε0
o No correct answer
133. A conductor in electrostatic equilibrium has the following properties:
· 1. The electric field is zero everywhere inside the conductor. 2. Any net charge on the conductor resides entirely on its surface. 3. The electric field just outside the conductor is perpendicular to its surface and has a magnitude σ / ε0, where σ is the surface charge density at that point. 4. On an irregularly shaped conductor, the surface charge density is greatest where the radius of curvature of the surface is the smallest.
o 1. The electric field is zero everywhere inside the conductor. 2. Any net charge on the conductor resides partially on its surface, partially inside the conductor. 3. The electric field just outside the conductor is parallel to its surface and has a magnitude σ / ε0, where σ is the surface charge density at that point. 4. On an irregularly shaped conductor, the surface charge density is greatest where the radius of curvature of the surface is the smallest.
o 1. The electric field is non zero everywhere inside the conductor. 2. Any net charge on the conductor resides entirely on its surface. 3. The electric field just outside the conductor is perpendicular to its surface and has a magnitude σ / ε0, where σ is the surface charge density at that point. 4. On an irregularly shaped conductor, the surface charge density is greatest where the radius of curvature of the surface is the biggest.
o 1. The electric field is zero everywhere inside the conductor. 2. Any net charge on the conductor resides entirely inside the conductor. 3. The electric field just outside the conductor is perpendicular to its surface and has a magnitude σ / ε0, where σ is the surface charge density at that point. 4. On an irregularly shaped conductor, the surface charge density is smallest where the radius of curvature of the surface is the smallest.
o No correct answer
134. When a positive test charge q 0 is moved between points A and B in an electric field E, the change in the potential energy of the charge–field system is:
· 
o 
o 
o 
o No correct answer
135. The potential difference ∆ V between points A and B in an electric field E is defined as:
· 
o 
o 
o 
o No correct answer
136. The potential difference between two points A and B in a uniform electric field E, where s (d=|s|) is a vector that points from A to B and is parallel to E is:
· ∆V=- Ed
o ∆V=0
o ∆V= Ed
o ∆V=- Edsinθ
o No correct answer
137. Which statements are correct?
· An equipotential surface is one on which all points are at the same electric potential. Equipotential surfaces are perpendicular to electric field lines.
o An equipotential surface is one on which all points are at the same electric potential. Equipotential surfaces are parallel to electric field lines.
o An equipotential surface is one on which all points are not at the same electric potential. Equipotential surfaces are perpendicular to electric field lines.
o An equipotential surface is one on which all points are at the same electric potential. Equipotential surfaces are perpendicular to gravitation field lines.
o No correct answer
138. If we define V = 0 at rA = ∞ the electric potential due to a point charge at any distance r from the charge is:
· 
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