On a cold winter day, the outside temperature is -20°C and the inside temperature is
maintained at 20°C. There is a net heat flow to the outside through the walls, roof, etc.,
of 25 kW. What is the rate of increase of the entropy of the universe as a result of this?
A) 13 W/K
B) 25 W/K
C) 85 W/K
D) 99 W/K
E) 0 W/K
An object is located 2.6 m in front of a plane mirror. The image formed by the mirror
appears to be
A) 1.3 m in front of the mirror.
B) on the mirror’s surface.
C) 1.3 m behind the mirror’s surface.
D) 2.6 m in front of the mirror.
E) 2.6 m behind the mirror’s surface.
One sometimes hears reference to a “20-kiloton” bomb. What does this mean?
A) It means 20,000 tons of nuclear explosive is used in the bomb.
B) It means that the number of “fissile” nuclei is equal to the number of trinitrotoluene
molecules in 20,000 tons of TNT explosive.
C) It means that the total weight of the bomb (not just the uranium) is 20,000 tons.
D) It means that the energy released by the bomb is equal to the energy released when
20,000 tons of TNT is exploded.
E) This refers to the maximum pressure generated by the bomb when it explodes.
When star light passes by the sun
A) it is unaffected by the sun.
B) it is deflected away from the sun.
C) it is deflected toward the sun.
D) it is absorbed by the sun.
Kirchhoff’s voltage rule for a closed loop is an example of
A) conservation of energy.
B) conservation of charge.
C) conservation of momentum.
D) conservation of force.
The monthly (30 days) electric bill included the cost of running a central
air-conditioning unit for 2.0 hr/day at 5000 W, and a series connection of ten 60 W light
bulbs for 5.0 hr/day. How much did these items contribute to the cost of the monthly
electric bill if electricity costs 8.0 per kWh?
A) $21.30
B) $39.50
C) $31.20
D) $13.20
E) $12.30
A dielectric material such as paper is placed between the plates of a capacitor holding a
fixed charge. What happens to the electric field between the plates?
A) no change
B) becomes stronger
C) becomes weaker
D) reduces to zero
E) cannot be determined without additional information
What is the ionization energy of singly ionized helium?
A) 54.4 eV
B) 13.6 eV
C) 27.2 eV
D) 6.80 eV
E) 36.4 eV
An unknown resistor is wired in series and an ammeter and a voltmeter are placed in
parallel across both the resistor and the ammeter. This network is then placed across a
battery. If one computes the value of the resistance by dividing the voltmeter reading by
the ammeter reading, the value obtained
A) is the true resistance.
B) is greater than the true resistance.
C) is less than the true resistance.
D) could be anything. It depends on other factors.
In order to construct a voltmeter from a galvanometer, one normally would
A) use a very large shunt resistor.
B) use a very small shunt resistor.
C) use a very small series resistor.
D) use a very large series resistor.
What is the mass of a woman who weighs 110 lb?
A) 50 kg
B) 55 kg
C) 73 kg
D) 110 kg
E) 242 kg
A carbon resistor has a resistance of 18 Ω at a temperature of 20°C. What is its
resistance at a temperature of 120°C? (The temperature coefficient of resistivity for
carbon is -5.0 x 10-4 /C.)
A) 18 Ω
B) 17 Ω
C) 16 Ω
D) 15 Ω
E) 14 Ω
Two asteroids, of the same mass, have a gravitational potential energy U. If a third
asteroid, of the same mass, moves toward them, to a position such that the distances
between the three asteroids are the same, the gravitational potential energy of the
system will have changed by
A) 4U.
B) 2U.
C) 3U.
D) U.
E) 5U.
A object is 20 cm in front of a concave mirror, and the image is 5.0 cm in front of the
mirror. What is the focal length of the mirror?
A) 0.25 cm
B) 25 cm
C) 6.7 cm
D) 4.0 cm
E) 2.1 cm
A fan blade, whose diameter is 1.0 m, is turning with an angular velocity of 2.0 rad/s.
What is the tangential velocity of a point on the tip of the blade?
A) 2.0 m/s
B) 5.0 cm/s
C) 1.0 m/s
D) 0.50 m/s
E) 1.5 m/s
When multiplying several quantities, the number of significant digits in the result must
always be
A) larger than the number of significant digits in the most accurate of the quantities.
B) equal to the number of significant digits in the most accurate of the quantities.
C) equal to the average number of significant digits in the most and least accurate of the
quantities.
D) equal to the number of significant digits in the least accurate of the quantities.
E) smaller than the number of significant digits in the least accurate of the quantities.
A metal surface is illuminated with blue light and electrons are ejected at a given rate
each with a certain amount of energy. If the intensity of the blue light is increased,
electrons are ejected
A) at the same rate, but with more energy per electron.
B) at the same rate, but with less energy per electron.
C) at an increased rate with no change in energy per electron.
D) at a reduced rate with no change in energy per electron.
A quark can have a charge of
A) -3/2 e.
B) -e/2.
C) -1/3 e.
D) -e/4.
E) -3/4 e.
A plano-convex lens is to have a focal length of 40 cm. It is made of glass of index of
refraction 1.65. What radius of curvature is required?
A) 36. cm
B) 26. cm
C) 13. cm
D) 32. cm
E) 44. cm
A car traveling 20 m/s rounds an 80 m radius horizontal curve with the tires on the
verge of slipping. How fast can this car round a second curve of radius 320 m? (Assume
the same coefficient of friction between the car’s tires and each road surface.)
A) 40 m/s
B) 70 m/s
C) 30 m/s
D) 1.6 m/s
E) 80 m/s
A beam of red light and a beam of violet light each deliver the same power on a surface.
For which beam is the number of photons hitting the surface per second the greatest?
A) the red beam
B) the violet beam
C) The number of photons per second is the same for both beams.
D) This cannot be answered without knowing just what the light intensity is.
A concave mirror with a radius of 20 cm creates a real image 30 cm from the mirror.
What is the object distance?
A) 50 cm
B) 20 cm
C) 15 cm
D) 7.5 cm
E) 5.0 cm
FIGURE 8-2
An 82.0 kg-diver stands at the edge of a light 5.00-m diving board, which is supported
by two pillars 1.60 m apart, as shown in Fig. 8-2.
(a) Find the force exerted by pillar A.
(b) Find the force exerted by pillar B.
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) 4.2 x 10-19 J
C) 2.0 x 10-19 J
D) 2.0 eV
E) 3.2 J
Scientists were led to postulate the existence of the neutrino in order to
A) maintain the conservation of energy and of momentum in beta decay.
B) provide a mechanism for quark production.
C) account for alpha decay.
D) explain the intense radiation emitted by quasars.
The banking angle in a turn on the Olympic bobsled track is not constant, but increases
upward from the horizontal. Coming around a turn, the bobsled team will intentionally
“climb the wall,” then go lower coming out of the turn. Why do they do this?
A) to reduce the g-force on them
B) to increase the g-force on them
C) to prevent the bobsled from turning over
D) to take the turn at a faster speed
E) to give the team better control, because they are able to see ahead of the turn
The Michelson-Morley experiment was designed to measure
A) the relativistic mass of the electron.
B) the relativistic momentum of the electron.
C) the relativistic energy of the electron.
D) the velocity of the Earth relative to the ether.
E) the acceleration of gravity on the Earth’s surface.
An old bone sample contains 321. grams of carbon and its activity is 947. decays/min.
(5730. yr half life of Carbon-14)
(a) How many thousand years old is the sample?
(b) What will be the activity of the sample 2000. yrs from now?
Charges 6.8 μC, 6.1 μC, and -1.5 μC are brought from infinity to the respective vertices
of an equilateral triangle with 11. cm sides.
(a) How much energy did it take to move the charges to the triangle vertices?
(b) What is the potential at the center of the triangle?
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 x 1013
B) 1.25 x 1019
C) 2.50 x 1013
D) 2.50 x 1019
E) 0
If the mass of a 1.0 kg book could be entirely converted into electrical energy, how
many Kw-h would that generate?
State the Law of Conservation of Linear Momentum.
Four 20. Ω resistors are connected in parallel. What is the equivalent resistance?
A 50. Ω resistor is placed in series with a 40. mH inductor. At what frequency will the
current in such a circuit lag the applied voltage by exactly 45?
The electron spin quantum number can take on what values?
Give examples of four quantities which are vectors.
What charge appears on the plates of a 2.00 μF capacitor when it is charged to 100. V?
Fig. 2-5 represents the velocity of a particle as it travels along the x-axis. At what value
of t is the instantaneous acceleration equal to zero m/s2?
An airplane with an airspeed of 120. km/h is headed 30.0 East of North in a wind
blowing due West at 30. km/h. What is the groundspeed of the plane?
State the Second Law of Thermodynamics.
How many moles are there in 2.0 kg of copper? (The atomic weight of copper is 63.5
and its specific gravity is 8.9.)
My hair dryer is rated at 1500. watts and my television only uses 100. watts, so why do
I pay more for electricity for my TV than for my hair dryer in a year?
A person tries to heat up her bath water by adding 5.0 L of water at 80°C to 60 L of
water at 30°C. What is the final temperature of the water?
Why can longitudinal earthquake waves go straight through the center of the Earth but
transverse waves cannot?
A bullet moving at 244. m/s strikes a tree and penetrates a distance of 8.34 mm before
stopping. What was the average acceleration of the bullet as it slowed?
Complete the following nuclear decay equation:
Po* → Po + ________
Red light with a wavelength of 650. nm travels from air into a liquid with an index of
1.33. What is the frequency and wavelength in the liquid?