Final answers, Fall 2004.

The following are all the answers, sorted in alphabetic order, but not the same as any of the 3 forms of the exam which were distributed.

  1. A 10-kilogram block with an initial velocity of 10 m/s slides 10 meters across a horizontal surface and comes to rest. It takes the block 2 seconds to stop. The stopping force acting on the block is about: A) 5 N. B) 10 N. C) 25 N. D) 50 N. E) none of these.
  2. A 10-N falling object encounters 10 N of air resistance. The net force on the object is: A) 0N. B) 4 N. C) 6 N. D) 10 N. E) none of these.
  3. A 1-kg chunk of putty moving at 1 m/s collides with and sticks to a 5-kg bowling ball initially at rest. The bowling ball and putty then move with a momentum of A) 0 kg m/s. B) 1 kg m/s. C) 2 kg m/s. D) 5 kg m/s. E) more than 5 kg m/s.
  4. A 1-kg rock that weighs 9.8 N is thrown straight upward at 20 m/s. Neglecting air resistance, the net force that acts on it when it is half way to the top of its path is: A) less than 9.8 N. B) 9.8 N. C) more than 9.8 N.
  5. A ball is thrown upwards. Neglecting air resistance, what initial upward speed does the ball need to remain in the air for a total time of 10 seconds?: A) about 50 m/s B) about 60 m/s C) about 80 m/s D) about 100 m/s E) about 110 m/s
  6. A ball rolls down a hill mainly because of: A) an unbalanced torque. B) an unbalanced force. C) its rotational inertia. D) angular momentum.
  7. A balloon is buoyed up with a force equal to the A) density of surrounding air. B) atmospheric pressure. C) weight of air it displaces. D) weight of the balloon and contents. E) all of these.
  8. A baseball player bats a ball with a force of 1000 N. The ball exerts a reaction force against the bat of A) more than 1000 N. B) less than 1000 N. C) 1000 N.
  9. A bullet is fired straight down from the top of a high cliff. Neglecting air resistance, the acceleration of the bullet in meters per second per second is A) 9.8. B) more than 9.8. C) less than 9.8.
  10. A car accelerates from rest for 5 seconds until it reaches a speed of 20 m/s. What is the car's acceleration in meters per second per second? A) 1 B) 2 C) 3 D) 4 E) 5
  11. A car traveling along the highway needs a certain amount of force exerted on it to stop it in a certain distance. More stopping force is required when the car has A) more momentum. B) more mass. C) less stopping distance. D) all of these. E) none of these.
  12. A cello string 0.75 m long has a fundamental frequency of 220 hertz. The speed of a wave on the string is: A) 165 m/s. B) 220 m/s. C) 294 m/s. D) 330 m/s. E) none of these.
  13. A certain radioactive isotope placed near a Geiger counter registers 160 counts per second. Eight hours later, the counter registers 10 counts per second. What is the half life of the isotope?: A) 8 hours B) 6 hours C) 4 hours D) 2 hours E) none of these
  14. A certain transformer doubles input voltage. If the primary coil has 10 A of current, then the current in the secondary coil is: A) 2 A. B) 5 A. C) 10 A. D) 25 A. E) none of these.
  15. A chain reaction grows when the average number of liberated neutrons which go on to cause further fissions is : A) zero. B) less than one. C) one. D) greater than one.
  16. A device that transforms mechanical energy into electrical energy is a: A) generator. B) motor. C) transformer. D) magnet. E) none of these.
  17. A flower pot of mass m falls from rest to the ground below, a distance h. Which statement is correct?: A) The speed of the pot when it hits the ground is proportional to h. B) The KE of the pot when it hits the ground is proportional to h. C) The KE of the pot when it hits the ground does not depend on m. D) The speed of the pot when it hits the ground depends on m. E) None of these is correct.
  18. A golf ball moving forward with 1 unit of momentum strikes and bounces backward off a heavy bowling ball that is initially at rest and free to move. The bowling ball is set in motion with a momentum of: A) less than 1 unit. B) more than 1 unit. C) 1 unit. D) not enough information.
  19. A heater uses 20 A when used in a 110-V line. If electric power costs 10 cents per kilowatt hour, the cost of running the heater for 10 hours is: A) $0.22. B) $0.55. C) $2.20. D) $5.50. E) none of these.
  20. A heavy block at rest is suspended by a vertical rope. When the block is accelerated upward by the rope, the rope tension: A) increases. B) decreases. C) remains the same.
  21. A horse exerts 500 N of force on a heavy wagon. The wagon pulls back on the horse with an equal force. The wagon still accelerates because: A) these forces are not an action-reaction pair. B) nevertheless there is still an unbalanced force on the wagon. C) the horse pulls on the wagon a brief time before the wagon reacts. D) the wagon does not accelerate because these forces are equal and opposite. E) unlike the horse, it is not alive.
  22. A hydraulic press multiplies a force by 100. This multiplication is done at the expense of A) the distance through which the force acts. B) the mechanism providing the force. C) energy, which is divided by 100. D) the time through which the force acts, which is multiplied by 100. E) none of these.
  23. A lump of energy associated with light is called a A) quantum. B) photon. C) both of these. D) neither of these.
  24. A mixture of cyan and yellow pigments appearsA) orange.B) green.C) magenta.D) blue.E) blackish brown.
  25. A negatively charged rod is brought near a metal can that rests on a wood table. You touch the opposite side of the can momentarily with your finger. The can is then: A) positively charged. B) negatively charged. C) uncharged. D) charged the same as it was.
  26. A neon atom has a larger atomic number than a helium atom. At the same temperature and pressure, how does the speed of sound in helium gas compare to the speed of sound in neon gas?A) greater in neon than in helium B) greater in helium than in neon C) the same in both gasesD) depends on the frequency of the sound generated
  27. A nucleon has the least mass in the nucleus of: A) hydrogen. B) iron. C) lead. D) uranium. E) plutonium.
  28. A package falls off a truck that is moving at 30 m/s. Neglecting air resistance, the horizontal speed of the package just before it hits the ground is A) more than 30 m/s. B) zero. C) less than 30 m/s but larger than zero. D) about 30 m/s. E) more information needed for an estimate.
  29. A paint pigment that absorbs red light and gives off blue light A) is phosphorescent. B) is fluorescent. C) is used in lasers.
    D) is polarized. E) doesn't exist.
  30. A person weighs less at the equator than at the poles. The main reason for this has to do with the A) influence of the sun, moon, and all the planets. B) tidal bulges. C) spin of the Earth. D) higher temperature at the equator, and the expansion of matter.
  31. 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
  32. A quantity of water has more entropy when it is A) frozen ice. B) boiling
  33. A ring and a disk, initially at rest, roll down a hill together. The one to reach the bottom firstA) is the ring.B) is the disk.C) depends on the masses.D) depends on the relative rotational inertias.E) both reach the bottom at the same time.
  34. A river 100 m wide flows due south at 1 m/s. A boat that goes 1 m/s relative to the water is pointed due east as it crosses from the west bank. The boat reaches the east bank : A) due east of where it started. B) 141 m farther south than where it started. C) 100 m farther south than where it started. D) 100 m farther north than where it started.
  35. A rock is thrown upward at 50 degrees with respect to the horizontal. As it rises, its horizontal component of velocity(neglect air resistance E): A) increases. B) remains unchanged. C) decreases.
  36. A sheet of paper can be withdrawn from under a container of milk without toppling it if the paper is jerked quickly. This best demonstrates that: A) the milk carton has no acceleration. B) there is an action-reaction pair of forces. C) gravity tends to hold the milk carton secure. D) the milk carton has inertia. E) none of these.
  37. A sheet of red paper will look black when illuminated with A) cyan light. B) red light. C) yellow light. D) magenta light. E) none of these.
  38. A spring is stretched 10 cm by a suspended 1-kg block. If two such springs side by side are used to suspend the block, so each spring supports half the weight of the block, then each spring will stretch: A) 5 cm. B) 10 cm. C) 20 cm. D) 30 cm. E) none of these.
  39. A substance can absorb heat energy by the process of: A) conduction. B) convection. C) radiation. D) all of these.
  40. A torque acting on an object tends to produce: A) equilibrium. B) rotation. C) linear motion. D) velocity. E) a center of gravity.
  41. A truck is moving at constant velocity. Inside the storage compartment, a rock is dropped from the midpoint of the ceiling and strikes the floor below. The rock hits the floor A) exactly below the midpoint of the ceiling. B) behind the midpoint of the ceiling. C) ahead of the midpoint of the ceiling. D) more information is needed to solve this problem. E) none of these.
  42. A very massive object A and a less massive object B move toward each other under the influence of gravitation. Which force, if either, is greater? A) Both forces are the same. B) the force on A C) the force on B
  43. A wave having a frequency of 1000 hertz vibrates at A) less than 1000 cycles per second. B) more than 1000 cycles per second. C) 1000 cycles per second.
  44. A wave oscillates up and down two complete cycles each second. If the wave travels an average distance of 6 meters in one second, its wavelength is: A) 0.5 m. B) 1 m. C) 2 m. D) 3 m. E) 6 m.
  45. A woman on the surface of the Earth has a mass of 50 kilograms and a weight of 490 newtons. If the woman were floating freely inside a space habitat far away from Earth, she would haveA) less weight and more mass.B) less weight and the same mass.C) less weight and less mass.D) more weight and less mass.E) none of these.
  46. About how many octaves are present between 100 hertz and 1600 hertz?: A) 4 B) 5 C) 6 D) 7 E) 8
  47. According to Neils Bohr, an electron in an excited state could give off: : A) at most a single photon until the atom was excited again. B) several photons in a series of transitions to the ground state. C) a continuous cascade of photons for a high-level transition. D) none of these.
  48. According to Newton, doubling the distance between two interacting objects: A) divides by 2 the gravitational force between them. B) multiplies by 2 the gravitational force between them. C) divides by 4 the gravitational force between them. D) multiplies by 4 the gravitational force between them.
  49. According to the uncertainty principle, the more we know about a particle's momentum, the less we know about its: A) kinetic energy. B) mass C) speed. D) location. E) none of these.
  50. All deposits of natural uranium contain appreciable amounts of A) gold. B) iron. C) lead. D) all of these. E) none of these particularly.
  51. All other things being the same, strings that have more mass than other strings will produce A) the same frequency notes. B) higher frequency notes. C) lower frequency notes.
  52. Alternating current is normally produced by a A) generator. B) battery. C) both of these. D) neither of these.
  53. An ampere is a unit of electrical: A) pressure. B) current. C) resistance. D) all of these. E) none of these.
  54. An apple weighs 1 N. When held at rest above your head, the net force on the apple is: A) 0 N. B) 0.1 N. C) 1 N. D) 9.8 N. E) none of these.
  55. An electric motor and electric generator are A) very similar devices. B) entirely different devices.
  56. An industrial flywheel has a greater rotational inertia when most of its mass is: A) nearest the rim. B) nearest the axis. C) uniformly spread out as in a disk.
  57. An iron block is placed in a furnace where it is heated and consequently expands. In the expanded condition, its density: A) is less. B) is the same. C) is more.
  58. An object will normally be a net radiator of energy when its internal energy is: A) more than that of its surroundings. B) less than that of its surroundings. C) neither of these, because internal energy is not temperature.
  59. An umbrella tends to move upwards on a windy day principally because: A) air gets trapped under the umbrella, warms, and rises. B) buoyancy increases with increasing wind speed. C) air pressure is reduced over the curved top surface. D) all of these.
  60. An ungloved fist will do more damage to a jaw than a gloved fist. The reason for this is that the ungloved fist A) exerts a larger force on the jaw. B) has less air resistance on it. C) delivers a larger impulse to the jaw. D) none of these.
  61. As an object freely falls downward, its A) velocity increases. B) acceleration increases. C) both of these. D) none of these.
  62. Astronomers can tell whether a star is approaching or receding from earth by: A) its temperature. B) its change in temperature. C) its absorption spectra. D) the Doppler effect. E) all of these.
  63. Atmospheric pressure is caused by the: A) density of the atmosphere. B) weight of the atmosphere. C) temperature of the atmosphere. D) effect of the sun's energy on the atmosphere.
  64. Atoms heavier than hydrogen were made by A) radiant energy conversion. B) nuclear fusion. C) radioactivity. D) photosynthesis. E) none of these.
  65. Before ice can form on a lake, all the water in the lake must be cooled to: A) zero degrees C. B) 4 degrees C.
  66. Blow on your hand with your open mouth and you feel the warmth of your breath. Pucker your lips so your breath expands as you blow and your breath is A) neither warmer nor cooler. B) cooler. C) warmer still.
  67. Both black and white road surfaces absorb sunlight. At the end of a sunny day the warmer road surface will be: A) the black surface. B) the white surface. C) neither -- there is no difference.
  68. Bullets are fired from an airplane in the forward direction of motion. The momentum of the airplane will be: A) decreased. B) unchanged. C) increased.
  69. Caruso is said to have made a crystal chandelier shatter with his voice. This is a demonstration of A) an echo. B) interference. C) sound refraction. D) resonance. E) beats.
  70. Color is seen by A) the rods in the eye. B) the cones in the eye. C) both of these. D) neither of these.
  71. Colors seen when gasoline forms a thin film on water are a demonstration of A) polarization. B) dispersion. C) refraction. D) reflection. E) interference.
  72. Compared to a neutron bouncing off a carbon nucleus, a neutron bouncing off a hydrogen nucleus loses A) the same amount of speed. B) less speed. C) more speed.
  73. Compared to the huge force that attracts an iron tack to a strong magnet, the force that the tack exerts on the magnet is A) relatively small. B) equally huge C) more information is needed.
  74. Complementary colors are two colors that : A) look good together. B) are additive primary colors. C) are subtractive primary colors. D) produce white light when added together. E) are right for each other.
  75. Consider a metal ring with a gap cut in it. When the ring is heated, the gap: A) becomes narrower. B) becomes wider. C) retains its size.
  76. Consider a sample of water at 0 degrees C. If the temperature is slightly increased, the volume of the water: A) increases. B) decreases. C) remains the same.
  77. Consider a steaming aluminum soda-pop can that contains a small amount of boiling water. When it is quickly inverted into a bath of cooler water the can is dramatically crushed by atmospheric pressure. This occurs because the pressure inside the can is rapidly reduced by: A) contact with the relatively cool water. B) sudden slowing of the air and steam molecules inside. C) condensation of steam inside. D) reduced internal energy. E) rapid conduction of heat to the relatively cool water.
  78. Consider plane waves incident upon a barrier with a small opening. After passing through the opening, the waves: A) continue as plane waves. B) fan out. C) converge. D) become polarized. E) all of these.
  79. Deuterium and tritium are both A) forms of hydrogen. B) isotopes of the same element. C) both of these. D) neither of these.
  80. Double the frequency of a sound and you halve itsA) wavelength.B) speed.C) amplitude.D) all of these.E) none of these.
  81. Doubling the thickness (diameter) of a rope will multiply its strength byA) 1/2.B) 1.C) 2.D) 3.E) 4.
  82. During a single period, the distance traveled by a wave is A) one-half wavelength .B) one wavelength. C) two wavelengths.
  83. Early Greeks knew (to a fair approximation) A) the size of the moon. B) the size of the Earth. C) the Earth-moon distance.D) all of the above.E) none of the above.
  84. Electric potential, measured in volts, is the ratio of electric energy to amount of electric: A) current. B) resistance. C) charge. D) voltage. E) none of these.
  85. Electrons are made to flow in a wire when there is: A) an imbalance of charges in the wire. B) more potential energy at one end of the wire than the other. C) a potential difference across its ends.
  86. Entropy measures A) temperature at constant pressure. B) temperature as volume increases. C) temperature as pressure increases. D) temperature at constant volume. E) messiness.
  87. Evaporation is a cooling process because A) of conduction and convection. B) heat is radiated during the process. C) the more energetic molecules are able to escape the liquid. D) the temperature of the remaining liquid decreases. E) none of these.
  88. Fissioning helium would yield a net: A) absorption of energy. B) release of energy. C) neither absorption nor release of energy.
  89. For light, a red shift indicates that the light source is moving: A) toward you. B) away from you. C) at right angles to you. D) actually, all of these. E) none of these.
  90. Four amperes of current exist in the primary coil of a transformer. The voltage across the primary coil is 110 V. What is the power output of the secondary coil? A) 27.5 W B) 110 W C) 440 W D) 880 W E) not enough information to say
  91. Generally speaking, the larger a nucleus is, the greater its: A) stability. B) instability. C) neither stability nor instability.
  92. Heat energy is measured in units of A) calories. B) joules. C) both of these.
  93. How many Joules of energy are in one kilowatt-hour?: A) 1  B) 60  C) 60,000 D) 3.6 million E) none of these
  94. Ice tends to form at the A) surface of bodies of water. B) bottom of bodies of water.
  95. If a satellite's radial velocity is zero at all times, its orbit must be A) parabolic. B) elliptical. C) geosynchronous. D) circular.
  96. If a volume of air is warmed, it expands. If a volume of air expands, it: A) warms. B) cools. C) neither warms nor cools.
  97. If an alpha particle and a beta particle have the same energy, which particle will penetrate farther into an object?: A) alpha particle B) beta particle C) They both penetrate the same distance.
  98. If the polar icecaps melted, the resulting water would spread over the entire earth. This new mass distribution would tend to make the length of a day: A) longer. B) shorter. C) stay the same.
  99. If the primary of a transformer were connected to a dc power source, the transformer would have a voltage output: A) at a higher efficiency than with an ac source. B) the same. C) that is also dc. D) only while being connected or disconnected. E) none of these.
  100. If you double the frequency of a vibrating object, its period: A) doubles. B) halves. C) is quartered.
  101. In a mixture of hydrogen gas, oxygen gas, and nitrogen gas, the molecules with the greatest average speed are those of: A) hydrogen. B) oxygen. C) nitrogen D) all will have the same average speed at the same temperature.
  102. In both fission and fusion, mass: A) is created from energy of other forms. B) is changed to the form of kinetic energy. C) remains the same.
  103. In the Bohr model of hydrogen, discrete radii and energy states result when an electron circles the atom in an integral number of A) wave frequencies.B) de Broglie wavelengths.C) diffraction patterns.D) none of these.
  104. In the double-slit experiment with electrons, the electrons arrive at the screen in a: A) particle-like way with a pattern that is particle-like. B) particle-like way with a pattern that is wave-like. C) wave-like way with a pattern that is particle-like. D) wave-like way with a pattern that is wave-like.
  105. In the relationship E = hf for a photon emitted from an atom, the symbol E is used to represent the energy: A) of the emitted photon. B) difference between atomic energy states producing the photon. C) both of these. D) neither of these.
  106. Inhaling helium increases the pitch of your voice. The reason for this is that sound travels A) slower in helium than in air.B) faster in helium than in air.C) the same speed in helium, but the wavelength is greater.
  107. Iridescent colors seen in the pearly luster of an abalone shell are due to A) dispersion. B) polarization. C) diffraction. D) Interference E) refraction.
  108. It is correct to say that impulse is equal to: A) momentum. B) the change in momentum. C) the force multiplied by the distance the force acts. D) all of these. E) none of these.
  109. It is possible to totally convert a given amount of mechanical energy into heat. A) True. B) False.
  110. It takes 40 J to push a large box 4 m across a floor. Assuming the push is in the same direction as the move, what is the magnitude of the force on the box? A) 4 N B) 10 N C) 40 N D) 160 N E) none of these
  111. It takes 6 seconds for a stone to fall to the bottom of a mine shaft. How deep is the shaft?: A) about 60 m B) about 120 m C) about 180 m D) more than 200 m
  112. It's impossible for a hydrogen atom to emit an alpha particle. : A) True. B) False.
  113. Light is emitted when an electron: A) is boosted to a higher energy level. B) makes a transition to a lower energy level. C) neither of these.
  114. Light refracts when traveling from air into glass because light: A) has greater intensity in air than in glass. B) has greater intensity in glass than in air. C) has greater frequency in air than in glass. D) has greater frequency in glass than in air. E) travels slower in glass than in air.
  115. Metal detectors, like the ones used at airports, are activated byA) electric fields.B) magnetic fields.C) electromagnetic induction.D) alternating current.
  116. One half second after starting from rest, a freely-falling object will have a speed of about A) 20 m/s. B) 10 m/s. C) 5 m/s. D) 2.5 m/s. E) none of these.
  117. One object has twice as much mass as another object. The first object also has twice as much A) inertia. B) velocity. C) volume. D) gravitational acceleration. E) all of these.
  118. Plutonium is not found in any appreciable amounts in natural ore deposits because it: A) is artificially created. B) is chemically inert. C) is a gas at room temperature. D) has a short half life. E) none of these.
  119. Pour a liter of water at 40 degrees C into a liter of water at 20 degrees C and the final temperature of the two becomes: A) less than 30 degrees C. B) at or about 30 degrees C. C) more than 30 degrees C.
  120. Power is transmitted at high voltages because the corresponding current in the wires is: A) also high to deliver appreciable power to distant places. B) low so that overheating of the wires is minimized. C) both of these. D) neither of these.
  121. Put a pipe over the end of a wrench when trying to turn a stubborn nut on a bolt, to effectively make the wrench handle twice as long, you'll multiply the torque by A) two. B) four. C) eight.
  122. Rainbows exist because light is A) refracted. B) reflected. C) both of these. D) neither of these.
  123. Red sunsets are due to lower frequencies of light that : A) are scattered from larger particles in the air. B) are refracted from larger particles in the air. C) are reflected by clouds and relatively large particles in the air. D) survive being scattered in the air. E) appear reddish orange to the eye. remain unchanged
  124. Room temperature on the Kelvin scale is about: A) 100 K. B) 200 K. C) 300 K. D) 400 K. E) more than 400 K.
  125. Several paper clips dangle from the north pole of a magnet. The induced pole in the bottom of the lowermost paper clip is a A) north pole. B) south pole. C) north or south pole - no difference really.
  126. Some alpha particles fired through a gold foil bounce backward by : A) making direct hits with gold atoms. B) electrostatic repulsion when close to gold nuclei. C) electrostatic repulsion with the electron clouds of gold atoms. D) all of these. E) none of these.
  127. Some of a wave's energy dissipates as heat. In time, this will reduce the wave's: A) speed. B) wavelength. C) amplitude. D) frequency. E) period.
  128. Systems that are left alone, tend to move toward a state of A) less entropy. B) no entropy. C) more entropy.
  129. The atomic mass number of an element is the same as the number of its : A) protons. B) neutrons. C) nucleons. D) none of these.
  130. The attraction of a person's body toward the Earth is called weight. The reaction to this force is: A) the person's body pushing against the Earth's surface. B) the Earth's surface pushing against the person's body. C) the person's body pulling on the Earth. D) none of these.
  131. The average speed of a horse that gallops a distance of 10 kilometers in a time of 30 minutes is: A) 10 km/h. B) 20 km/h. C) 30 km/h. D) more than 30 km/h.
  132. The brightest color emitted by the sun isA) red.B) orange.C) yellow-green.D) green-blue.E) violet.
  133. The center of mass of a human body is located at a point: A) which is fixed, but different for different people. B) that is always directly behind the belly button. C) that changes as a person bends over. D) none of these.
  134. The complementary color of blue is : A) red. B) green. C) yellow. D) cyan. E) magenta.
  135. The electric field around an isolated electron has a certain strength 1 cm from the electron. The electric field strength 2 cm from the electron is: A) half as much. B) the same. C) twice as much. D) four times as much. E) none of these.
  136. The energy release in both fission and fusion is mainly in the form of A) a combination of alpha, beta, and gamma radiation. B) kinetic energy of fragments. C) gamma radiation. D) beta radiation. E) alpha radiation
  137. The first law of thermodynamics is a restatement of the: A) principle of entropy. B) law of heat addition. C) Carnot cycle. D) conservation of energy. E) none of these.
  138. The glare seen from water is largely A) vertically polarized. B) non polarized. C) horizontally polarized.
  139. The half-life of a radioactive substance is INDEPENDENT of A) the number (if large enough) of atoms in the substance. B) the temperature of the substance. C) the age of the substance. D) whether the substance exists in an elementary state or in a compound. E) all of these.
  140. The ideal efficiency for a heat engine operating between the temperatures of 227 degrees C and 27 degrees C is: A) 20%. B) 25%. C) 40%. D) 88%. E) none of these.
  141. The intensity of cosmic rays bombarding the Earth's surface is largest at the A) poles. B) equator. C) mid-latitudes.
  142. The lowest temperature possible in nature is: A) 0 degrees C. B) -273 degrees C. C) 4 K.
  143. The newton is a unit of A) force. B) mass. C) density. D) inertia.
  144. The photoelectric effect best demonstrates the A) wave nature of light. B) particle nature of light. C) both of these. D) none of these.
  145. The planet Earth loses heat mainly by: A) conduction. B) convection. C) radiation. D) all of these.
  146. The pressure in a liquid depends on liquid: A) density. B) depth. C) both of these. D) neither of these.
  147. The quality of a musical note has to do with itsA) loudness.B) frequency.C) harmonics.D) amplitude.E) all of these.
  148. The reason a life jacket helps you float is A) the jacket has the same density as an average human. B) the density of both you and the jacket together is less than your density alone. C) if you sink, the jacket sinks. D) the jacket repels water. E) the jacket makes you weigh less.
  149. The reason that buoyant force acts upward on a submerged object is that: A) it acts in a direction to oppose gravity. B) if it acted downward, nothing would float. C) the weight of fluid displaced reacts with an upward force. D) upward pressure against the bottom is greater than downward pressure against the top of the submerged object.
  150. The source of electrons in an ordinary electrical circuit isA) a dry cell, wet cell or battery.B) the back emf of motors.C) the power station generator.D) the electrical conductor itself.E) none of these.
  151. The source of the Earth's natural heat is : A) molten-hot lava. B) pressure on the Earth's core. C) radioactive decay in the Earth's core. D) solar energy in the form of fossil fuels.
  152. The spacings between double-slit interference fringes is increased if the slits are: A) closer together. B) farther apart. C) narrower. D) wider. E) none of these.
  153. The speed of light in the void between molecules in glass is A) the same as its speed in a vacuum. B) less than its speed in a vacuum. C) more than its speed in a vacuum.
  154. The tapered shape of the parts of the wheels that ride on railroad tracks allows opposite wheels to A) in effect, vary their diameters. B) both of these. C) travel at different linear speeds for the same rotational speed. D) neither of these.
  155. The temperature at the bottom of Lake Tahoe, high in the Sierra Nevada Mountains in California, at this moment is A) below 4 degrees C. B) above 4 degrees C. C) 4 degrees C. D) uncertain.
  156. The white light emitted by a fluorescent lamp is provided by the: A) mercury vapor in the lamp. B) phosphors on the inner surface of the lamp. C) high temperature of the glowing gas. D) filtering effect of the glass tubing.
  157. There is a greater proportion of carbon(14) in: A) new bones. B) old bones. C) same in each.
  158. To increase the temperature of 50 grams of water by 1 Celsius degree requires A) 1 calorie. B) 50 calories. C) none of these.
  159. Two 5000-kg freight cars roll toward each other (one at 1 m/s, the other at 2 m/s) on a level track. Thus before they collide one car's kinetic energy is 2500 J and the other's is 10,000 J. After they collide (and couple together) their total kinetic energy is: A) 1250 J. B) 2500 J. C) 7500 J. D) 10,000 J. E) 12,500 J. (By momentum conservation, final velocity is1/2 m/, so 1/2 x 10,000 x 1/4 J = 1250J)
  160. Two equal sized buckets are filled to the top with water. One of the buckets has a piece of wood floating in it, making its total weight : A) less than the weight of the other bucket. B) equal to the weight of the other bucket. C) more than the weight of the other bucket.
  161. Two identical blocks of iron, one at 10 degrees C and the other at 20 degrees C, are put in contact. Suppose the cooler block cools to 5 degrees C and the warmer block warms to 25 degrees C. This would violate the: A) 1st law of thermodynamics. B) 2nd law of thermodynamics. C) both of these. D) neither of these.
  162. Two identical gliders slide toward each other on an air track. One moves at 1 m/s and the other at 2 m/s. They collide and stick. The combined mass moves at: A) 1/2 m/s. B) 1/3 m/s. C) 1/6 m/s. D) 3/4 m/s. E) 1.5 m/s.
  163. Two objects, A and B, have the same size and shape, but A is twice as heavy as B. When they are dropped simultaneously from a tower, they reach the ground at the same time, but A has a greater: A) speed. B) acceleration. C) momentum. D) all of these. E) none of these.
  164. Two protons attract each other gravitationally and repel each other electrically. By far the greater is A) the electrical repulsion. B) the gravitational attraction. C) neither - they are the same.
  165. U-235 and Pu-239 are both: A) radioactive isotopes. B) fissionable isotopes. C) heavier than lead. D) all of these. E) none of these.
  166. Ultraviolet light is A) produced by crossed Polaroids. B) more energetic than X-rays. C) present everywhere. D) electromagnetic energy. E) none of these.
  167. Unlike a transverse wave, a longitudinal wave has: A) no amplitude. B) no frequency. C) no wavelength. D) no speed. E) ...a longitudinal wave has all of these.
  168. Using 1000 J of work, a toy elevator is raised from the ground floor to the second floor in 20 seconds. How much power does the elevator use?: A) 20 W B) 50 W C) 100 W D) 1000 W  E) 20,000 W
  169. Waves diffract the most when their wavelength isA) short.B) long.C) both diffract the same.
  170. What is the acceleration of a car that maintains a constant velocity of 100 km/hr for 10 seconds?: A) 0 B) 10 km/hr s C) 10 m/hr s D) 1000 km/hr s
  171. What is the power rating of a light bulb if 0.8 A flow through it when it is connected to a 120-volt outlet? A) 12 W B) 15 W C) 60 W D) 96 W E) 120 W
  172. What prevents satellites such as the space shuttle from falling?: A) gravity B) the absence of air drag C) Nothing; they're falling continuously all around the Earth.
  173. When a bimetallic bar made of copper and iron strips is heated, the bar bends toward the iron strip. The reason for this is: A) iron gets hotter before copper . B) copper gets hotter before iron. C) copper expands more than iron. D) iron expands more than copper. E) none of these.
  174. When a nucleus emits a beta particle, its atomic number A) increases by 1.B) decreases by 1.C) increases by 2.D) decreases by 2.E) none of these.
  175. When a pair of 1-ohm resistors are connected in series, their combined resistance is: A) 1 ohm, and when connected in parallel, 2 ohms. B) 2 ohms, and when in parallel, 1 ohm. C) 1/2 ohm, and when in parallel, 2 ohms. D) 2 ohms, and when in parallel, 1/2 ohm. E) none of these.
  176. When a rock thrown straight upwards gets to the exact top of its path, its: A) velocity is zero and its acceleration is zero. B) velocity is zero and its acceleration is about 10 meters per second per second. C) velocity is about 10 m/s and its acceleration is zero. D) velocity is about 10 m/s and its acceleration is about 10 meters per second per second. E) none of these.
  177. When a twirling ice skater brings her arms inward, her rotational speed: : A) increases. B) decreases. C) remains the same.
  178. When a volume of air expands against the environment and no heat enters or leaves, the air temperature will: A) increase. B) decrease. C) remain unchanged.
  179. When an ice cube in a glass of water melts, the water level: : A) rises. B) falls. C) remains the same.
  180. When an object is partly or wholly immersed in a liquid, it is buoyed up:: A) by a force equal to its own weight. B) by a force equal to the weight of liquid displaced. C) and floats because of Archimedes principle. D) but nevertheless sinks. E) none of these.
  181. When an object is raised above the ground it gains a certain amount of potential energy. If the same object is raised twice as high it gains: A) four times as much potential energy. B) twice as much potential energy. C) neither of these.
  182. When gas in a container is squeezed to half its volume and the temperature remains the same, the gas pressure: A) halves. B) doubles. C) quadruples. D) remains the same.
  183. 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 these.
  184. When water vapor condenses on the inside of a window, the room becomes slightly: A) warmer. B) cooler. C) neither warmer nor cooler.
  185. When we say an appliance "uses up electricity," we really are saying that: A) current disappears. B) electric charges are dissipated. C) the main power supply voltage is lowered. D) electrons are taken out of the circuit and put somewhere else. E) electron kinetic energy is changed into heat.
  186. When white light goes from air into water, the color that refracts the most is: A) red. B) orange. C) green. D) violet. E) all refract the same amount.
  187. When work is done by a system and no heat added to it, the temperature of the system: A) increases. B) decreases. C) remains unchanged.
  188. Which force binds atoms together to form molecules?: A) gravitational B) nuclear C) electrical D) centripetal E) none of these
  189. Which has zero acceleration? An object: A) at rest. B) moving at constant velocity. C) in mechanical equilibrium. D) all of these. E) none of these.
  190. Which involves the larger number of calories?: A) the condensation of 1 gram of steam at 100 degrees Celsius to 100 degrees Celsius water B) the change of state of 1 gram of 100-degree-Celsius water to 1 gram of ice at absolute zero C) Both involve the same number of calories.
  191. Which is more dangerous, touching a faulty 110-volt light fixture, or a Van de Graaff generator charged to 100,000 volts? A) touching the generator B) touching the light fixture C) Touching both are about equally dangerous.
  192. Which of the following are consequences of light's traveling at different speeds in different media? A) internal reflection B) rainbows C) mirages D) all of these E) none of these
  193. Which of the following is not a vector quantity?: A) velocity  B) speed C) acceleration D) None are vector quantities. E) All are vector quantities.
  194. Which of these atoms has the greatest amount of electrical charge in its nucleus?: A) helium B) carbon C) iron D) gold E) uranium
  195. Which radiation has no electric charge associated with it?: A) alpha rays B) beta rays C) gamma rays D) all of these E) none of these
  196. Which will warm up quicker in sunlight? A) a piece of clear glass B) a piece of colored glass C) both the same
  197. Wind blowing over the top of a hill A) does not affect atmospheric pressure there. B) increases atmospheric pressure there. C) decreases atmospheric pressure there.
  198. You know that you can safely stand on the overhanging end of a heavy plank that rests on a table. How far out depends on your mass and the mass of the plank. Suppose you can stand on the end of a plank that overhangs the edge of the supporting table 1/4 its total length. Then how massive is the plank compared to your mass?: A) 1/2 your mass B) the same as your mass C) 1 1/2 your mass D) twice your mass E) 4 times your mass
  199. You wish to photograph the image of your little sister, who is standing 2 meters from a plane mirror. Holding the camera beside her head, you should set the distance for: A) 1 meter. B) 2 meters. C) 3 meters. D) 4 meters. E) none of these.
  200. Your weight is: A) actually your mass. B) the gravitational attraction between you and the Earth. C) a property of mechanical equilibrium. D) all of these. E) none of these.