conceptual physics final
When water at 4 degrees C is heated slightly it expands. When water at 4 degrees C is cooled slightly, it A) contracts. B) expands. C) neither contracts nor expands.
B) expands.
High pitched sound has a high A) speed. B) frequency. C) number of partial tones. D) All of the above choices are correct. E) None of the above choices are correct.
B) frequency.
For increased atmospheric pressure, the boiling temperature of a liquid A) goes down. B) goes up. C) remains at 100 degrees C.
B) goes up.
When liquids change to a solid state, they A) absorb energy. B) release energy. C) neither absorb nor release energy. D) both absorb and release energy.
B) releases energy.
A main difference between gravitational and electric forces is that electrical forces A) attract. B) repel or attract. C) obey the inverse-square law. D) act over shorter distances. E) are weaker.
B) repel or attract.
Housing and natural animal insulation works because A) the insulating materials are poorer heat conductors than air. B) the insulating materials trap air and prevent convection. C) the insulating materials prevent radiation D) the insulating materials reflect radiation
B) the insulating materials trap air and prevent convection.
A floating object oscillates up and down 2 complete cycles in 1 second as a water wave of wavelength 5 meters passes by. The speed of the wave is A) 2 m/s. B) 5 m/s. C) 10 m/s. D) 15 m/s. E) none of these
C) 10 m/s.
The current through a 10-ohm resistor connected to a 120-V power supply is A) 1 A. B) 10 A. C) 12 A. D) 120 A. E) none of these
C) 12 A.
The amplitude of a particular wave is 1 meter. The top-to-bottom distance of the disturbance is A) 0.5 m. B) 1 m. C) 2 m. D) none of these
C) 2 m.
The fundamental frequency of a violin string is 440 hertz. The frequency of its second harmonic is A) 220 hertz. B) 440 hertz. C) 880 hertz. D) None of the above choices are correct.
C) 880 hertz.
Freezing is a _______ ______ that requires energy ________ for the melting system. A) phase transition; input B) chemical change; input C) phase transition; release D) chemical change; release
C) phase transition; release
Stretch a copper wire so that it is thinner and the resistance between its ends A) decreases. B) remains unchanged. C) increases.
C) increases
Heat a copper wire and its electric resistance A) decreases. B) remains unchanged. C) increases.
C) increases.
The phenomenon of beats results from sound A) refraction. B) reflection. C) interference. D) all of these E) none of these
C) interference.
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.
C) protons than electrons.
Sound travels faster in A) air. B) water. C) steel. D) a vacuum. E) Sound travels at about the same speed in all of the above media.
C) steel.
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.
E) 16 N.
An explosion occurs 34 km away. Since sound travels at 340 m/s, the time it takes for the sound to reach you is A) 0.1 second. B) 1 second. C) 10 seconds. D) 20 seconds. E) more than 20 seconds.
E) more than 20 seconds.
Consider water that freezes into ice when put in your freezer, so the water goes from being disordered to being relatively ordered. Please explain if the freezing of the ice violated the second law of thermodynamics.
No the second law is not violated; the entropy of the universe still increased. Although locally the ice froze and its entropy went down, there is a greater entropy increase due to the heat being dissipated outward from the freezer coils. So when you add it all up, the entropy of the universe increased.
If the speed of light in a medium is 1.5 × 108 m/s, the medium's index of refraction is A) 2.0. B) 0.67. C) 1.0. D) 1.5. E) None of the above
A) 2.0.
Suppose you try to cool your home in the summer by letting heat flow from your house to your neighbor's home. You will A) Not get far, because of the zeroth law of thermodynamics B) Not get far, because of the first law of thermodynamics C) Have a cool house in a couple hours D) Have a warmer house in a couple hours
A) Not get far, because of the zeroth law of thermodynamics
At the same time an astronaut on the moon sees a solar eclipse, observers on Earth see A) a lunar eclipse. B) a solar eclipse. C) no eclipse at all.
A) a lunar eclipse.
Materials generally become warmer when light is A) absorbed by them. B) reflected by them. C) transmitted by them. D) all of these E) none of these
A) absorbed by them.
The sources of X-rays and gamma rays, respectively, are A) electron clouds and the atomic nucleus. B) the atomic nucleus and electron clouds. C) both electron clouds. D) both the atomic nucleus. E) none of these
A) electron clouds and the atomic nucleus.
When a light beam emerges from water into air, the average light speed A) increases. B) decreases. C) remains the same.
A) increases.
Electrons on the surface of a conductor will arrange themselves such that the electric field A) inside the conductor is zero B) tends toward the state of minimum energy C) is maximum D) None of the above
A) inside the conductor is zero
Color depends on what characteristic of light? A) its frequency B) its amplitude C) both of these
A) its frequency
A 100-Watt lamp glows brighter than a 25-Watt lamp. The electrical resistance of the 100-Watt lamp must be A) less. B) greater. C) the same.
A) less.
The atomic number of an element is the same as the number of its A) protons. B) neutrons. C) nucleons. D) neither of these
A) protons.
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.
A) quadruples.
When a gas is changed to a liquid state, the gas A) releases energy. B) absorbs energy. C) neither releases nor absorbs energy. D) both releases and absorbs energy.
A) releases energy.
In an electric circuit, the safety fuse is connected to the circuit in A) series. B) parallel. C) either series or parallel.
A) series.
Which of the following is fundamentally different from the others? A) sound waves B) X-rays C) gamma rays D) light waves E) radio waves
A) sound waves
Sunburns are produced by A) ultraviolet light. B) visible light. C) infrared light. D) all of these E) none of these
A) ultraviolet light.
Your image in a plane mirror is A) virtual. B) real. C) both of these D) neither of these
A) virtual.
When a 60-watt light bulb is connected to a 120-volt source the current in the light bulb is A) 0.25 A. B) 0.5 A. C) 2 A. D) 4 A. E) more than 4 A.
B) 0.5 A.
What is the frequency of an electromagnetic wave that has a wavelength of 300,000 km? A) less than 1 Hz B) 1 Hz C) more than 1 Hz
B) 1 Hz
When a 10-V battery is connected to a resistor, the current in the resistor is 2 A. What is the resistor's value? A) 2 ohms B) 5 ohms C) 10 ohms D) 20 ohms E) more than 20 ohms
B) 5 ohms
What do electrons have that protons always have in equal magnitude? A) mass B) charge C) energy D) all of these E) none of these
B) charge
As more lamps are put into a series circuit, the overall current in the power source A) increases. B) decreases. C) stays the same.
B) decreases.
Object and image for a plane mirror lie A) along the same plane. B) equal distances from the mirror. C) at right angles to each other. D) all of these
B) equal distances from the mirror.
The energy of a photon depends on its A) speed. B) frequency. C) amplitude. D) all of these E) none of these
B) frequency.
A mixture of cyan and yellow pigments appears A) orange. B) green. C) magenta. D) blue. E) blackish brown.
B) green.
Generally speaking, the larger a nucleus is, the greater its A) stability. B) instability. C) neither stability nor instability
B) instability.
Compared to the resistance of two resistors connected in series, the same two resistors connected in parallel have A) more resistance. B) less resistance. C) the same resistance.
B) less resistance.
When two lamps are connected in parallel to a battery, the electrical resistance that the battery senses is A) more than the resistance of either lamp. B) less than the resistance of either lamp. C) none of these
B) less than the resistance of either lamp.
Compared to its average speed in air, the average speed of a beam of light in glass is A) more. B) less. C) the same.
B) less.
Compared to ultraviolet waves, the wavelength of infrared waves is A) shorter. B) longer. C) the same.
B) longer.
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
B) makes a transition to a lower energy level.
A lunar eclipse occurs when the A) sun passes into Earth's shadow. B) moon passes into Earth's shadow. C) Earth passes into the sun's shadow. D) Earth passes into the moon's shadow.
B) moon passes into Earth's shadow.
Electromagnetic waves consist of A) compressions and rarefactions of electromagnetic pulses. B) oscillating electric and magnetic fields. C) particles of light energy. D) high-frequency gravitational waves.
B) oscillating electric and magnetic fields.
When ultraviolet light is incident upon glass, atoms in the glass A) are forced into vibration. B) resonate. C) pass the light energy along practically undiminished. D) freely absorb and re-emit most of the ultraviolet light.
B) resonate
Different colors are dispersed by a prism because different colors in the prism have different A) frequencies. B) speeds. C) directions. D) energies. E) none of these
B) speeds.
Fourier discovered that periodic waves can be represented by A) a series of non-periodic waves. B) the summation of a series of simple sine waves. C) a binary code. D) pulses of the same amplitude.
B) the summation of a series of simple sine waves.
Light will almost always travel from one place to another along a path of least A) distance. B) time. C) effort. D) expense. E) complication.
B) time.
The power dissipated in a 4-ohm resistor carrying 3 A is A) 7 W. B) 18 W. C) 36 W. D) 48 W. E) not enough information to say
C) 36 W.
Which of these electromagnetic waves has the shortest wavelength? A) radio waves B) infrared waves C) X-rays D) ultraviolet waves E) visible light waves
C) X-rays
In a simple circuit containing a bulb, energy is given to the moving charges by A) the bulb. B) the wires. C) a generator. D) none of these
C) a generator.
Light travels fastest in A) warm air. B) cool air. C) a vacuum.
C) a vacuum.
A single raindrop illuminated by sunshine disperses A) a single color. B) either low-, middle-, or high-frequency colors in most cases. C) all the colors of the rainbow.
C) all the colors of the rainbow.
What color light is transmitted by a piece of blue glass? A) red B) white C) blue D) yellow E) orange
C) blue
Rainbows exist because light is A) reflected. B) refracted. C) both of these D) neither of these
C) both of these
When an alpha particle is ejected from a nucleus, the nucleus then has less A) mass. B) charge. C) both of these D) neither of these
C) both of these
To receive an electric shock there must be A) current in one direction B) moisture in the electrical device being used C) difference in potential across part or all of body D) None of the above
C) difference in potential across part of all of body
If the sun were to disappear right now, we wouldn't know about it for 8 minutes because it takes 8 minutes A) for the sun to disappear. B) to operate receiving equipment in the dark. C) for light to travel from the sun to the Earth. D) all of these E) none of these
C) for light to travel from the sun to the Earth.
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
C) gamma rays
What is the wavelength of an electromagnetic wave that has a frequency of 1 hertz? A) less than 1 m B) 1 m C) more than 1 m
C) more than 1 m
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
C) nucleons.
On some early automobiles both headlights went out when one bulb burned out. The headlights must have been connected in A) parallel. B) perpendicular. C) series. D) haste.
C) series.
Refraction results from differences in light's A) frequency. B) incident angles. C) speed D) all of these E) none of these
C) speed
Compared to radio waves, the velocity of visible light waves in a vacuum is A) less. B) more. C) the same.
C) the same.
Consider light energy that is momentarily absorbed in glass and then re-emitted. Compared to the absorbed light, the frequency of the re-emitted light is A) considerably less. B) slightly less. C) the same. D) slightly more. E) considerably more
C) the same.
The brightest color emitted by the sun is A) red. B) orange. C) yellow-green. D) green-blue. E) violet.
C) yellow-green
The complementary color of blue is A) red. B) green. C) yellow. D) cyan. E) magenta.
C) yellow.
If it takes 100 newtons of force to hold a 0.1-coulomb particle at rest in an electric field, the strength of the field there is A) 1N/C B) 10N/C C) 100N/C D) 1000N/C
D) 1000N/C
If you double the absolute temperature of a star, its power output increases by a factor of A) 2 B) 4 C) 8 D) 16
D) 16
If 0.8 A of current flow through a light bulb connected to a 120 V outlet, the power consumed is A) 12 W. B) 15 W. C) 60 W. D) 96 W. E) 120 W.
D) 96 W.
Electric potential and electric potential energy are A) one and the same in most cases B) two terms for the same concept C) Both A & B D) None of these
D) None of these
The greenish blue of water is evidence for the A) reflection of greenish-blue light. B) reflection of red light. C) absorption of greenish-blue light. D) absorption of red light. E) interaction between green and blue frequencies of light.
D) absorption of red light.
Amongst the following media, a beam of light travels fastest in A) glass. B) water. C) plastic. D) air. E) is the same in each of these
D) air.
The Doppler effect is characteristic of A) water waves. B) sound waves. C) light waves. D) all of the above choices E) none of the above choices
D) all of the above choices
Atoms can be excited by A) thermal agitation. B) electron impact. C) photon impact. D) all of these E) none of these
D) all of these
Interference is a property of A) light waves. B) sound waves. C) water waves. D) all of these E) none of these
D) all of these
The loudness of a musical sound is a measure of the sound wave's A) wavelength. B) frequency. C) speed. D) amplitude. E) all of these
D) amplitude.
A sheet of red paper will look black when illuminated with A) red light. B) yellow light. C) magenta light. D) cyan light. E) none of these
D) cyan light
Different colors of light correspond to different light A) velocities. B) intensities. C) polarities. D) frequencies. E) none of these
D) frequencies.
Most of the waves in the electromagnetic spectrum are A) red light. B) blue light. C) green light. D) invisible for humans.
D) invisible for humans.
When a gamma ray is emitted by a nucleus, the nucleus then has appreciably less A) mass. B) charge. C) both of these D) neither of these
D) neither of these
The half-life on an isotope is one day. At the end of three days, how much of the isotope remains? A) none B) one-half C) one-quarter D) one-eighth E) none of these
D) one-eighth
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
D) the Doppler effect.
If you plug an electric toaster rated at 110 V into a 220-V outlet, the current in the toaster will be about A) half what it should be. B) the same as if it were plugged into 110 V. C) more than twice what it should be. D) twice what it should be.
D) twice what is should be.
Which color of light carries the most energy per photon? A) red B) green C) blue D) violet E) all the same
D) violet
The highest frequency light of those below is A) red. B) green. C) blue. D) violet. E) all the same
D) violet.
The electric power of a lamp that carries 2 A at 120 V is A) 1/6 watts. B) 2 watts. C) 60 watts. D) 20 watts. E) 240 watts.
E) 240 watts.
What condition must exist between two points in a conductor in order to maintain a flow of charge? A) a steady magnetic field B) a high resistance C) a switch connected in series D) All of the above choices are correct. E) None of the above choices are correct.
E) None of the above choices are correct.
The half-life of a radioactive substance is INDEPENDENT of A) the number (if large enough) of atoms in the substance. B) whether the substance exists in an elementary state or in a compound. C) the temperature of the substance. D) the age of the substance. E) all of these
E) all of these
Ice is put in a cooler to cool the contents. To speed up the cooling process, the ice can be A) wrapped in newspaper. B) drained of ice water periodically. C) kept out of contact with the food. D) kept in one solid chunk. E) covered with salt.
E) covered with salt.
The main difference between a radio wave and a sound wave is their different A) frequencies. B) wavelengths. C) energies. D) amplitudes. E) modes of travel
E) modes of travel.
A red crab very deep in water, where sunlight is dim, appears A) red. B) orange. C) cyan. D) brown. E) no color - black.
E) no color - black.
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.
E) travels slower in glass than in air.
If you double the radiating surface area of a star, its power output increases by a factor of A) 2 B) 4 C) 8 D) 16
A) 2
The beat frequency produced when a 240 hertz tuning fork and a 246 hertz tuning fork are sounded together is A) 6 hertz. B) 12 hertz. C) 240 hertz. D) 245 hertz. E) None of the above choices are correct.
A) 6 hertz
A shiny, white transparent surface prevents heat transfer because A) It has emissivity of zero and reflects all light that strikes it. B) It has emissivity of 1 and reflects all light that strikes it. C) It has emissivity of zero and absorbs all light that strikes it. D) It has emissivity of 1 and absorbs all light that strikes it.
A) It has emissivity of zero and reflects all light that strikes it.
Sound waves can interfere with one another so that no sound results. A) True B) False C) Either true or false, depending on the air temperature.
A) True
"Two objects in thermal equilibrium with a third object are in thermal equilibrium with each other." Which Law of Thermodynamics is this? A) Zeroth B) First C) Second D Third
A) Zeroth
The fact that desert sand is very hot in the day and very cold at night is evidence that sand has A) a low specific heat. B) a high specific heat. C) no specific heat.
A) a low specific heat.
The electrical force between charges is strongest when the charges are A) close together. B) far apart. C) The electric force is constant everywhere
A) close together.
As we become older, the frequency range of human hearing A) decreases. B) increases. C) remains relatively constant
A) decreases.
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.
A) electron.
Compared to a glass of ice water with ice in it, a glass of plain ice-cold water without ice on a warm day will warm up A) faster. B) slower. C) in the same amount of time. D) None of the above choices are true.
A) faster.
When you touch a cold piece of ice with your finger, energy flows A) from your finger to the ice. B) from the ice to your finger. C) actually, both ways.
A) from your finger to the ice
Compressions and rarefactions are characteristic of A) longitudinal waves. B) transverse waves. C) both longitudinal and transverse waves. D) none of the above.
A) longitudinal waves.
A node is a position of A) minimum amplitude. B) maximum amplitude. C) half amplitude.
A) minimum amplitude
If the specific heat of water were lower than it is, ponds in the cold of winter would be A) more likely to freeze. B) less likely to freeze. C) neither more nor less likely to freeze.
A) more likely to freeze.
Which of the following is not a transverse wave? A) sound B) light C) radio D) all of these E) none of these
A) sound
Ice tends to form first at the A) surface of bodies of water. B) bottom of bodies of water. C) surface or bottom depending on the water depth.
A) surface of bodies of water.
In a longitudinal wave the compressions and rarefactions travel in A) the same direction. B) opposite directions. C) a vacuum.
A) the same direction.
The fact that a thermometer "takes its own temperature" illustrates A) thermal equilibrium. B) energy conservation. C) the difference between heat and internal energy. D) the fact that molecules are constantly moving.
A) thermal equilibrium.
The source of every sound is something that is A) vibrating. B) moving. C) accelerating. D) undergoing simple harmonic motion. E) a net emitter of energy.
A) vibrating.
When water vapor condenses on the inside of a window, the room becomes slightly A) warmer. B) cooler. C) neither warmer nor cooler.
A) warmer.
Suppose you walk on red-hot coals with bare feet. If bits of the coals do not stick to your feet, it would be best if your feet are A) wet. B) dry. C) warm. D) cold. E) very hot.
A) wet.
Double the frequency of a sound and you halve its A) wavelength. B) speed. C) amplitude. D) all of these E) none of these
A0 wavelength.
The frequency of the second hand on a clock is A) 1 hertz. B) 1/60 hertz. C) 60 hertz.
B) 1/60 hertz.
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.
B) 10 V.
Which could burn the most? A) 100 g of water at 100 degrees C B) 100 g of steam at 100 degrees C C) Both would be equally damaging.
B) 100 g of steam at 100 degrees C
A wave having a frequency of 1000 hertz vibrates at A) less than 1000 cycles per second. B) 1000 cycles per second. C) more than 1000 cycles per second.
B) 1000 cycles per second.
How many vibrations per second are associated with a 101-MHz radio wave? A) less than 101,000,000 B) 101,000,000 C) more than 101,000,000
B) 101,000,000
The approximate range of human hearing is A) 10 hertz to 10,000 hertz. B) 20 hertz to 20,000 hertz. C) 40 hertz to 40,000 hertz. D) Actually all of these - depends on the hearing ability of the person.
B) 20 hertz to 20,000 hertz.
Radio waves travel at the speed of light, 300,000 km/s. The wavelength of a radio wave received at 100 megahertz is A) 0.3 m. B) 3.0 m. C) 30 m. D) 300 m. E) none of these
B) 3.0 m
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. C) minus 32 degrees C. D) None of the above. Ice can form at the surface regardless of the water temperature below.
B) 4 degrees C.
Lead sinkers actually float on the surface of liquid mercury. Which takes up more space: 1 kg of mercury or 1 kg of lead? A) Mercury B) Lead C) Neither take up any space D) Not enough information is given
B) Lead
You fill two identical mugs with coffee, but the coffee in one mug is at a higher temperature than that in the other mug. You place the two mugs simultaneously in a microwave oven and turn it on briefly. As a result, you add 1 joule of thermal energy to each mug. Which mug experiences the larger increase in entropy (if any)? A) The two mugs experience equal increases in entropy. B) The mug containing the colder coffee experiences the larger increase in entropy. C) Neither mug experiences any increase in entropy. D) The mug containing the hotter coffee experiences the larger increase in entropy.
B) The mug containing the colder coffee experiences the larger increase in entropy.
Near the top of a mountain, water in an open pot boils at A) a higher temperature than at sea level. B) a lower temperature than at sea level. C) the same temperature as at sea level. D) None of the above choices are true.
B) a lower temperature than at sea level.
When a solid is changed to a liquid state, the solid A) releases energy. B) absorbs energy. C) neither releases nor absorbs energy. D) both releases and absorbs energy.
B) absorbs energy.
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.
B) at or about 30 degrees C.
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
B) away from you.
The gulf stream is one of nature's ways of transferring energy through A) conduction. B) convection. C) transmission. D) radiation.
B) convection.
Wind is one of nature's ways of transferring energy through A) conduction. B) convection. C) transmission. D) radiation.
B) convection.
Melting snow A) warms the surrounding air. B) cools the surrounding air. C) neither warms nor cools the surrounding air.
B) cools the surrounding air.
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.
B) decreases
Consider a sample of ice at 0 degrees C. If the temperature is decreased, the volume of the ice A) increases. B) decreases. C) stays the same.
B) decreases.
It is a hot summer day and your friend's apartment has no air conditioning. However, a brand new refrigerator lies unopened in the center of the living room. Being a creative person, your friend closes all the doors and windows of the apartment, unpacks the refrigerator, plugs it in, and turns it on. Your friend then opens the refrigerator door and uses a small fan to circulate the air past the refrigerator and throughout the room. After the refrigerator has operated for a few minutes, the average temperature in the room is A) lower than it was before. B) higher than it was before. C) the same as it was before and the temperature is uniform throughout the room. D) the same as it was before, but some regions are hotter and others are colder.
B) higher than it was before.
Which of the following normally warms up fastest when heat is applied? A) water B) iron C) glass D) wood E) All of the above choices are equally true
B) iron
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.
B) its charges have been rearranged.
When an iron ring is heated, the hole becomes A) smaller. B) larger. C) neither smaller nor larger. D) either smaller or larger, depending on the ring thickness.
B) larger.
Resonance can be looked at as forced vibration with the A) least amount of energy input. B) maximum amount of energy input. C) matching of wave amplitudes. D) matching of constructive and destructive interference. E) minimum beat frequency.
B) maximum amount of energy input.
In the poem "When You Are Old" by William Butler Yeats there is the following concluding line: "and bending down beside the glowing bars, murmur, a little sadly, how love fled and paced upon the mountains overhead and hid his face amid a crowd of stars." The glowing bars refer the metal bars that hold wood in a fireplace and they are transmitting heat energy by A) radiation only B) radiation and conduction. C) conduction only D) convection
B) radiation and conduction.
People fighting forest fires carry emergency tents that have shiny aluminum outer surfaces. If there is trouble, a fire fighter can lie under the tent to block the heat from burning trees overhead. The tent helps because A) conduction carries heat downward toward the fire fighter and the aluminum tent conducts that heat harmlessly into the ground. B) radiation carries heat downward toward the fire fighter and the aluminum tent reflects most of that radiation. C) convection carries heat downward toward the fire fighter and the aluminum tent blocks most of the heat carried by convection. D) both conduction and radiation carry heat downward toward the fire fighter and the aluminum tent blocks most of that heat.
B) radiation carries heat downward toward the fire fighter and the aluminum tent reflects most of that radiation.
Evaporation is a cooling process because A) heat is radiated during the process. B) the more energetic molecules are able to escape the liquid. C) the temperature of the remaining liquid increases. D) none of these
B) the more energetic molecules are able to escape the liquid.
Steam burns are more damaging than burns caused by boiling water because steam A) gives up additional energy when it condenses. B) has more energy per kilogram than boiling water. C) Choices A and B are both correct. D) Choices A and B are both incorrect.
C) Choices A and B are both correct.
Heat energy is measured in units of A) joules. B) calories. C) Choices A and B are both true. D) Kelvin
C) Choices A and B are both true.
Why are good thermal conductors generally good electric conductors also? A) Heat and electricity are the same things. B) The molecules in both don't move around very much. C) Electron motion is responsible for determining both properties. D) The answer depends on the specific metal.
C) Electron motion is responsible for determining both properties.
Which of the following quantities is not conserved? A) Energy B) Angular momentum C) Entropy D) Momentum
C) Entropy
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
C) F/2.
Why does an ice cube feel cold? A) Heat from your hand enters the cube by convection. B) Cold from the cube enters your hand by convection. C) Heat from your hand enters the cube by conduction. D) Cold from the cube enters your hand by conduction.
C) Heat from your hand enters the cube by conduction.
Which temperature scale has 273 as the boiling point of water? A) Fahrenheit B) Celsius C) No scale D) Kelvin
C) No scale
"The entropy of an isolated system never decreases." Which Law of Thermodynamics is this? A) Zeroth B) First C) Second D Third
C) Second
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.
C) a potential difference across its ends.
Refraction of sound can occur in A) air. B) water. C) both air and water. D) neither air nor water.
C) both air and water.
The first law of thermodynamics is a re - statement of the law of A) conservation of momentum B) thermal equilibrium C) conservation of energy D) averages
C) conservation of energy
When heat is added to boiling water, its temperature A) increases. B) decreases. C) does not change.
C) does not change.
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) more than the weight of the other bucket B) less than the weight of the other bucket C) equal to the weight of the other bucket D) None of the above
C) equal to the weight of the other bucket
An observer on the ground hears a sonic boom which is created by an airplane flying at a speed A) just below the speed of sound. B) equal to the speed of sound. C) greater than the speed of sound. D) All of the above choices are true. E) None of the above choices are true.
C) greater than the speed of sound.
The quality of a musical note has to do with its A) loudness. B) frequency. C) harmonics. D) amplitude. E) All of the above choices are correct.
C) harmonics.
In which one of these media does sound travel the fastest? A) water vapor B) water C) ice D) steam E) Sound travels the same speed in each of the above media.
C) ice
You are riding in a hot air balloon. You have not used the burner for some time and the balloon begins to sink. Assuming that no air is allowed to leave or enter the balloon, A) the average density of the balloon remained constant and the buoyant force on the balloon became less than its weight. B) the average density of the balloon became greater than the surrounding air and the buoyant force on the balloon remained constant. C) the average density of the balloon became greater than the surrounding air and the buoyant force on the balloon became less than its weight. D) the balloon became heavier.
C) the average density of the balloon became greater than the surrounding air and the buoyant force on the balloon became less than its weight.
When cooking a potato in a conventional oven it is useful to stick a nail in it, which makes it cook faster. This is because A) the nail is a good radiator of heat B) the nail promotes convection in the potato C) the nail is a good conductor of heat D) the nail gets much hotter than anything in the oven
C) the nail is a good conductor of heat
You are watching a science fiction movie where people on a space ship are traveling around the universe observing stars with different temperatures. Which of the following stars has the lowest surface temperature? A) A bluish star B) A yellowish star C) The sun D) A reddish star
D) A reddish star
Which temperature scale has 373 as the boiling point of water? A) Fahrenheit B) Celsius C) Centigrade D) Kelvin
D) Kelvin
A decibel is a measure of a sound's A) frequency. B) wavelength. C) speed. D) loudness. E) all of these
D) loudness.
Food cooked in boiling water at a mountain top cooks slower than when cooked at sea level. If the temperature under the pot of boiling water is increased, the food will cook A) faster at the mountain top. B) faster at sea level. C) faster at both places. D) no differently than it did before the increase.
D) no differently than it did before the increase.
A wave travels an average distance of 1 meter in 1 second with a frequency of 1 hertz. Its amplitude is A) less than 1 meter. B) 1 meter. C) more than 1 meter. D) not enough information to say
D) not enough information to say
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.
D) zero.