Physics and Human Affairs Test 2
A motionless object could have... A) speed B) elastic energy C) kinetic energy D) All of the above E) None of the above
Elastic energy
A "wave" could best be defined as... a) a transfer of molecules from one point to another along the direction of motion, where the molecules are bunched into groups b)a transfer of a disturbance from one point to another without any corresponding transfer of matter c) a transfer of a disturbance from one point to another without any corresponding transfer of energy d) a vibrational motion of matter e) an organized motion of matter from one point to another along the direction of motion of the wave
a transfer of a disturbance from one point to another without any corresponding transfer of matter
A water wave spreading out in a circle across the surface of a pond is an example of.... A) a two-dimensional wave B) a three-dimensional wave C) particle motion, or mass motion, rather than wave motion D) witchcraft E) a one-dimensional wave
a two-dimensional wave
Which of the following does not travel at light speed? A) light B) x-rays C) infra-red waves D) radio waves E) actually all of these travel at light speed
actually all of these travel at light speed
which of the following is not a possible energy source for a steam-electric generating plant? A) solar energy B) wood C) fissionable material such as uranium D) fossil fuels E) all of the above are possible energy sources
all of the above are possible energy sources
Why might excess CO2 in the atomosphere heat up the earth? A) because CO2 absorbs, or traps, ultra-violet radiation B) because CO2 reacts with and thus destroys the ozone layer C) because CO2 absorbs, or traps, infra-red radiation D) because CO2 increases Earth's "reflectivity" E) because CO2 is an important participant in the photosynthesis process
because CO2 absorbs, or traps, infra-red radiation
which of these, if used to replace gasoline as an automobile fuel, would not contribute to global warming? A) electricity from a nuclear power plant B) electricity from a coal-burning plant C) synthetic gasoline made from coal D) all of the above would contribute to global warming E) none of the above would contribute to global warming
electricity from a nuclear power plant
Entropy is best defined as... A) the capacity to do work B) microscopic disorganization C) microscopic organization D) energy that is due to its temperature E) energy that is due to chemical structure
microscopic disorganization
When a battery is used to light up a lightbulb,.... A) the amount of electrical current flowing into one side of the battery is equal to the amount flowing out of the other side B) electric charge builds up within the bulb, causing the bulb to light up C) electric charge builds up on hte battery terminals but none of it actually flows through the bulb D) some of the electrical current produced by the battery is consumed by the bulb, and the rest flows back into the battery E) all the electrical current produced by the battery is consumed by the bulb
the amount of electrical current flowing into one side of the battery is equal to the amount flowing out of the other side
There are no known exceptions to.... A) the law of conservation of energy B) Newton's law of motion C) Both of the above D) Nonsense--all physical principles have known exceptions
the law of conservation of energy
The "atomic number" of an element that appears in the periodic table of the elements represents... A) the number of nuclei in an atom of the element B) the number of atoms in a molecule of the element C) the number of protons in the nucleus of an atom of that element D) the number of electrons in the nucleus of an atom of that element E) the number of neutrons in the nucleus of an atom of that element
the number of protons in the nucleus of an atom of that element
The biggest reason why heat engines are far from 100% efficient is... A) the second law of thermodynamics B) gravitational forces C) the first law of thermodynamics D) gremlins E) friction
the second law of thermodynamics
a charged rod carrying a negative charge is brought near two spheres that are in contact with each other but insulated from the ground. If the two spheres are then seperated, what kind of charge will be on the spheres? A) the spheres do not get any charge B) the sphere near the charged rod becomes negative and the other becomes positive C) the sphere near the charged rod becomes positive and the other becomes negative D) not of the other choices is correct
the sphere near the charged rod becomes positive and the other becomes negative
You push your physics book across a table. the book weighs 8 N, you push with a steady 5 N force, and the force of friction against the book is 3 N. You push the book a distance of 2 m. The amount of work you do on the book is.... A)6 J B) 10 J C) 16 J D) zero E) impossible to tell without more information
10 J
A particular automobile operates at an efficiency of 10%. Suppose that 20 gallons of gasoline are put into the auto's tank. Of this 20 gallons, how much will be "wasted", i.e., how much will be consumed to produce exhaust heat and in other ways that do not actually get the car down the road? A) 18 gallons B)2 gallons C)19 gallons D) 20 gallons E) 10 gallons
18 gallons
Elizabeth lifts a 10N book from the floor to the table, a height of 2m. How much work does Elizabeth do? A) 5 watts B) 5 joules C) 20 joules D) Elizabeth does zero work E) 20 watts
20 Joules
A 100 W lightbulb has an energy efficiency of 5%. It is turned on for one minute. During this time, the visible radiant energy output of the lightbulb is.... A) 5700 J B) 300 J C) 6000 J D) impossible to determine because we do not know the voltage E) impossible to determine because we don't know the power
300 J
What should be the resistance of a light bulb in order for it to draw a 2 amp current when plugged into a 120-volt outlet? A) 1/30 ohm B) 60 ohms C) 1/60 ohms D) 30 ohms E) 480 ohms
60 ohms
Faraday's law tells us that... A) a changing electric field creates a magnetic field B) a changing magnetic field creates an electric field C) moving charges create magnetic fields D) charges create electric fields E) magnetic fields create electric fields
A changing magnetic field creates an electric field
One car is traveling twice as fast as a second car. How much more work can the first car do, compared to the second car, in smashing into a brick wall? A) twice as much B) the same amount as the second car C) three times as much D) four times as much E) all of the above
Four times as much
The "Isaac Newton of electromagnetism" was.... A) Maxwell B) Schiglegrueber C) Hertz D) Faraday E) Einstein
Maxwell
Is a fuel-cell vehicle described as a "heat engine?" A) No, because it converts electric energy directly into chemical energy B) Yes, because it uses chemical energy to create electric energy C) Yes, because it uses thermal energy to work D) No, because it converts chemical energy directly to electric energy E) Yes, because it uses thermal energy to produce electricity
No, because it converts chemical energy directly to electric energy
Do physicists consider electromagnetic fields to be "real"? A) No, because they are only an idea, imagined only by the human mind. B) Yes, because electromagnetic fields exert forces, even though they are not made of as atoms. C) Yes, because electromagnetic fields are made of atoms. D) No, because electromagnetic fields are not made of any material substance such as atoms. E) Yes, because electromagnetic fields contain energy, even though they are not made of atoms.
Yes, because electromagnetic fields contain energy, even though they are not made of atoms
Suppose an automobile's fuel could be makde to burn hotter without harming the engine's operation. Would you still get the same amount of useful work from each gallon of gasoline? A) it wouldn't make any difference, because the efficiency is related only to the amount of input energy, and not to the temperature of this energy B) You would get less work, because heat engines run less efficienctly when the input temperature is higher. C) YOu would get more work, because heat engines are more efficient at converting chemical energy into thermal energy when the temperature is higher D) You would get less work, because less chemical energy would be used at the higher temperature E) You would get more work, because heat engines are more efficient at converting thermal energy into work when the input temperature is higher
You would get more work, because heat engines are more efficient at converting thermal energy into work when the input temperature is higher
A day during which the atmosphere temperature was 40 degrees celcius would be described as... A) a hot day B) a cold day, but not freezing C) a nice day D) below freezing E) above boiling
a hot day
Chemical energy is transformed into gravitational energy when... A) a leaf undergoes photosynthesis B) a car accelerates C) a block slides downhill D) a person walks uphill E) water evaporates
a person walks uphill
A neutral atom loses one of its electrons. It is then.... A) either a negative or postive ion, depending on which electron was lost B) a positive ion C) a negative ion D) ashamed of itself E) a neutral ion
a positive ion
How does a permanent magnet work, i.e., what is the explanation of its magnetic effects? A) Electric charge is permanently seperated within the magnet, with positive static charge at one end and negative static charge at the other end of the magnet. B) the material of the magnet is highly ionized, with one type of ion residing on one end of the magnet and the other type of ion residing on the other end C) subatomic particles known as "magnetic poles" are placed on each end of the magnet, with one type of pole placed on one end and the other type on the other end D) magnets are a communist plot E) electrons orbiting individual atoms in the magnet are all aligned together so that their orbital motion produces a large overall effect
electrons orbiting individual atoms in the magnet are all aligned together so that their orbital motion produces a large overall effect
which part of the electromagnetic spectrum has the shortest wavelength? A) infrared B) ultraviolet C) radio D) visible E) gamma
gamma
Which of these energy transformations best describes the overall operation of a hydroeletric power plant? A) thermal E----> electromag E B) grav E----> electromag E C) electromag E---> grav E D) grav E---> therm E E) chem E---> electromag E
grav E---> electromag E
The energy transformation that occurs during downhill skiing is... A) grav E---> kin E +therm E B) chem E---> kin E +therm E C) kin E---> grav E D) grav E---> chem E E) kin E---> grav E + therm E
grav E---> kin E + therm E
Electrical and gravitational forces follow similar equations with one main difference:... A) electrical forces obey the inverse square law and gravitational forces do not B) gravitational forces are always attractive but electrical forces can be attractive or repulsive C) gravitational forces obey the inverse square law and electrical forces do not D) electrical forces repel and gravitational forces attract E) electrical forces attract and gravitational forces repel
gravitational forces always attractive but electrical forces can be attractive or repulsive
X-ray radiation typically comes from... A) charged particles moving within the nucleus B) thermal vibrations of molecules C) electrons moving along a metal antenna D) higher-energy electrons orbiting the nucleus in atoms E) none of the above
higher-energy electrons orbiting the nucleus in atoms
Which of the following is not a heat engine? A) automobile engine B) nuclear electric power plant C) hydro-electric generating plant D) steam locomotive E) coal-fired electric generating plant
hydro-electric generating plant
Which type of generating plant would you expect to be more energy efficient, steam-electric or hydroelectric? A) Hydroelectric, because it is not a heat engine and so is not restricted by the second law of thermodynamics B) Steam-electric, because it can have a very high operating temperature due to having a large and thick boiler C) Steam-electric, because there is so much more energy per ton in fossil fuels than in water behind a dam D) Hydro-electric, because the lake and river water provides natural cooling for the exhaust E) Hydroelectric, because there is so much energy in a large lake raised up behind a dam
hydroelectric, because it is not a heat engine and so is not restricted by the second law of thermodynamics
One situation in which the law of conservation of energy is violated is.... A) near black holes B) for atomic-sized objects C) for very fast-moving objects D) All of the above E) nonsense--no violations of this law have ever been observed
nonsense--no violations of this law have ever been observed
Electric generating plants are usually rated in "megawatts". This is a unit of..... A) both energy and work B) work C) power D) force E) energy
power
The atomic nucleus contains.... A) protons and electrons B) protons and neutrons C) yogurt D) neutrons and electrons E) protons only
protons and neutrons
When the distance between the two charges is doubled, the force between them is.... A) quadrupled B) reduced by a factor of the square root of two C) doubled D) reduced by a factor of 4 E) reduced by a factor of 3
reduced by a factor of 4
The figure above shows a marble rolling freely back and forth along a curved track. The track is positioned vertically. Assuming no friction and no air resistance, the total energy of the marble..... A) decreases when the marble rolls from A to B B) increases when the marble rolls from A to B C) remains the same when the marble rolls from A to B
remains the same when the marble rolls from A to B
James Prescott Joule's experiments, such as stirring a container full of liquid, showed that... A) the "Newtonian" energy forms [kinetic, gravitational, elastic] are conserved. B) radiant energy is actually a form of energy C) Mr. Joule did not know how to make a good batch of chili D) all forms of energy are conserved E) thermal energy is actually a form of energy
thermal energy is actually a form of energy
Suppose you charge two transparancies by rubbing and then hold them near each other but not touching. Regarding the electric and magnetic forces they exert on each other,... A) they will exert magnetic forces but not electric forces B) they will exert electric forces but not magnetic forces C) they will exert neither electric or magnetic forces because they are not in contact with each other D) they will exert netither electric nor magnetic forces because neither object is moving E) they will exert both electric and magnetic forces
they will exert electric forces but not magnetic forces
The "efficiency" of a heat engine is defined to be... A) thermal energy output divided by thermal energy input B) work output divided by thermal energy input C) thermal energy output divided by work input D) work output divided by thermal energy output
work output divided by thermal energy input
Are small ripples sent out across the surface of a lake truely "waves", as the word is used in physics? A) yes, because the water itself doesn't go anyplace but simply oscillates up and down B) no, because true water waves are longitudinal C) yes, because the water itself moves across the lake, away from the souce of the wave D) no, because the water itself doesn't go anyplace but simply oscillates up and down in one place E) no, because the water's motion is "mass motion", similar to the motion of a ball that has been thrown
yes, because the water itself doesn't go anyplace but simply oscillates up and down
