Exercises Flashcards
1
Q
What would be the ecological impact if the first trophic level were eliminated?
A
Without plants at the first trophic level, the other trophic levels could not exist and most species would die
2
Q
Why is the transfer of energy so inefficient when it moves between trophic levels
A
A great deal of heat energy is lost at each level by metabolic processes
3
Q
What is the main difference in diet for organisms at the second trophic level versus the third trophic level?
A
Organisms at the second trophic level consume plants and those at the third level consume organisms that eat plants.
4
Q
When a meteorite hits Earth, heat is generated. Which of the following statements best describes this process?
(a) Gravitational potential energy is converted into heat.
(b) Electrical potential energy is converted into heat.
(c) Chemical energy is converted into heat.
(d) Magnetic energy is converted into heat.
(e) Elastic potential energy is converted into heat.
A
When a meteorite hits Earth, heat is generated. Which of the following statements best describes this process?
(a) Gravitational potential energy is converted into heat.
5
Q
Under what circumstances could Earth be considered a closed system?
A
Under what circumstances could Earth be considered a closed system?
If the matter could not freely exchange with space outside the realm of the Earth, this would be a closed system
Obviously, the Earth is not a closed system because the Earth receives mass from space (meteorites, etc.) we also have the ability of sending satellites (mass) into other parts of the solar system outside of earth
6
Q
The first law of thermodynamics states:
A
while the kind of energy in a closed system can change, the total amount cannot.
7
Q
The conservation law in science states that:
A
the amount of energy in an isolated system stays the same.
8
Q
All popular weight loss diets are based on:
(a) the conservation law.
(b) increasing the exercise you do each day.
(c) the first law of thermodynamics.
(d) increasing protein intake.
(e) decreasing the exercise you do each day
A
All popular weight loss diets are based on:
(a) the conservation law.
(c) the first law of thermodynamics.
9
Q
What is the difference between food calories and a calorie as defined by physicists?
A
One food calorie is a kilocalorie (or 1000 calories as defined by physicists).
10
Q
In an isolated system, the total amount of what is conserved?
A
energy
11
Q
Compare the rate of global fossil fuel consumption to the rate of production of fossil fuel from organic materials.
A
There really is no good comparison because such an immense amount of time is required for the remains of plants and animals to be turned into fossil fuel compared with the way our population is increasingly using fossil fuels
12
Q
When a group of organisms get all their energy from the same source, we refer to them as
A
a trophic level
13
Q
Form the point of view of a system, the planet Earth is (system)
A
entirely open
14
Q
Let’s say that a partially closed system contains 5000 J now and that this system cannot gain any new energy but will lose at least 100 J per year. After 50 years, how much energy would you expect to find in this system?
A
0J
15
Q
Under normal circumstances, in order to maintain human body functions, you have to consume how many calories per day for each pound of body weight?
A
15
16
Q
The interior of the Earth has gained what fraction of its internal energy from radioactive decay processes?
A
One-half
17
Q
The main source of energy used in the United States is:
A
oil
18
Q
What type of energy-efficient automobile uses a gasoline engine to charge the car’s batteries that are in turn supplying energy to run the vehicle?
(a) Plug-in hybrid car (b) Electric car (c) Fuel cell car (d) Standard hybrid car
A
(a) Plug-in hybrid car
(d) Standard hybrid car
19
Q
If one were to introduce a fast moving molecule into a container of slower moving molecules the outcome will be:
A
(b) all molecules will end up traveling the same speed.
20
Q
Temperature is a measure of:
A
the average kinetic energy of the atoms within a substance.
21
Q
Absolute zero is defined as the temperature at which:
A
(b) all heat has been extracted from a substance.
22
Q
If one were to introduce a fast moving molecule into a container of slower moving molecules the outcome will be:
A
all molecules will end up traveling the same speed.
23
Q
The standard used to calibrate thermometers is:
A
pure water
24
Q
Which substance has the lowest specific heat capacity?
(a) Water (b) copper (c) ice (d) steam (e) both ice and copper
A
(b) copper
25
How is the dimension of time different from the dimensions defining space?
Time is the only dimension that has just one direction
26
Describe what happens at absolute zero.
Absolute zero (0 Kelvin) is the coldest theoretically attainable temperature; the temperature at which no more kinetic energy can be extracted from atoms or molecules
27
Explain why radiation is the only form of heat transfer energy that can travel through the emptiness of space
Radiation involves heat transfer by electromagnetic radiation like visible light. Light moves through empty space, for example, from the Sun to the Earth. Conduction and convection, in contrast, require a medium largely or completely filled with atoms or molecules to transfer heat.
28
A term that compares how vigorous atoms are moving in a substance is:
Temperature.
29
Energy can be transferred through a solid by:
(a) radiation only.
(b) both conduction and convection.
(c) both conduction and radiation.
(d) conduction only.
(e) convection only
(d) conduction only.
30
Through which material will heat be conducted the best?
(a) Steel
(b) water
(c) wood
(d) fur
(e) fat
steel
31
The heat island effect in cities creates convection cells:
(a) by drawing in cool moist air from the suburbs.
32
Insulation in the attic is used to reduce heat loss by:
(a) Conduction.
(b) Convection.
(c) Radiation.
(d) Efficiency.
(e) Heat death.
(a) Conduction.
(b) Convection.
33
Radiation is heat transfer by:
(a) electromagnetic waves of radiation
34
What is the primary way heat is transferred in a moving fluid?
Convection
35
How does the human body maintain its temperature?
When the body temperature rises, blood vessels near the surface of the skin dilate, so that the blood can carry more heat by convection to the surface where it is radiated away. When the body temperature falls, the opposite occurs.
36
How are urban heat islands responsible for extra rain in the city?
During the summer the parking lots and buildings heat more quickly than the surrounding non-urban areas. The rising warm air of the urban heat island pulls in cooler, moisture-laden air from the surrounding areas. This air ascends in the convection cell and produces clouds and rain over the city.
37
After mixing the ingredients for a salad, why do the ingredients (lettuce, tomato, cabbage, carrot, etc.) remain mixed? In other words, why do they not unmix themselves?
The statistical likelihood of this happening is so low that the chance of it happening is essentially zero.
38
In science, heat is commonly measured in what unit?
Calorie
39
The coldest possible temperature—absolute zero—is which of the following?
0 K
40
If the temperature of an object changes by 5\*C then it also changes by
5 K
41
Heat conduction works primarily because of which of the following reasons?
(a) In a closed system, energy is conserved.
(b) When two objects interact with each other, they exert equal but opposite forces on each other.
(c) The most likely outcome is for the particles making up the substance to go from a less likely state to a more likely state.
(d) In the absence of unbalanced forces, an object in motion will continue along with that motion
Heat conduction works primarily because of which of the following reasons?
(c) The most likely outcome is for the particles making up the substance to go from a less likely state to a more likely state.
42
In a room that is heated by a floor-mounted radiator near a wall, in which of the following locations would you find the coolest air?
(a) Near the ceiling directly above the radiator
(b) Near the ceiling at the top of the wall directly opposite the radiator
(c) Near the floor at the bottom of the wall directly opposite the radiator
(d) Near the floor at the top of the wall directly opposite the radiator
(c) Near the floor at the bottom of the wall directly opposite the radiator
43
name 2 reasons fiber glass is used for insulation
Conduction and convection are both inhibited by this material.
1) The thin fibers make conduction difficult.
2) The many small, unconnected pockets of air make convection difficult.
44
The mode of heat transfer that takes advantage of differences in density is:
convection
45
In the human body, where can convection occur?
circulating blood
46
Within a refrigerator, the amount of heat that is exhausted:
(a) is equal to the electrical energy drawn from the outlet.
(b) is equal to the thermal energy extracted from the inside of the refrigerator.
(c) is equal to the amount of heat drawn from the environment.
(d) is equal to the electrical energy drawn from the outlet plus the thermal energy extracted from the inside of the refrigerator
Within a refrigerator, the amount of heat that is exhausted:
(d) is equal to the electrical energy drawn from the outlet plus the thermal energy extracted from the inside of the refrigerator
47
3 statements of the second law of thermodynamics
Heat does not flow spontaneously from cold to hot
No engine can exclusively convert heat to work
Every isolated system tends toward disorder
48
Which would be the least effective insulation for your house?
(a) a meter-thick layer of trapped air
(d) a thin layer of wood
(b) a thin sheet of metal
(e) a single wall of cinder block
(c) thick bundles of straw or wool
(b) a thin sheet of metal
## Footnote
49
Which statement best represents the second law of thermodynamics?
(a) Heat will not flow spontaneously from a hot to a cold body.
(b) Every isolated system becomes more disordered with time.
(c) Scientists have constructed an engine that does nothing but convert heat to useful work. (d) The total amount of energy in the universe is constant.
(e) Energy may change from one form to another over and over again.
(b) Every isolated system becomes more disordered with time.
50
In the language of physics, what is an example of a low-temperature reservoir?
(a) a place where exhaust gasses are compressed
(b) an explosion of hot gasses
(c) pistons in the closed position
(d) atmosphere receiving a hot gas-air mixture.
(e) air and gas at a stable equilibrium
(d) atmosphere receiving a hot gas-air mixture.
51
define maximum theoretical efficiency
Efficiency (%) = [(Thot - Tcold) / Thot] x 100.
52
Why is convection a more efficient way to transfer heat versus conduction?
Heat is transferred by a moving fluid (for example, air or water) and this more efficiently distributes the heat energy
53
Why, after you get sunburned and you enter an air-conditioned building do you feel especially cold? Your answer should take into account the fact that blood vessels near the surface of your skin have dilated, allowing blood to move to the area of skin damage and begin repairs.
As the blood near the skin's surface comes into contact with the cool air, it rapidly loses heat to the surrounding air, so you perceive a drop in temperature.
54
Under what circumstances is a high-temperature area at 700 K considered to be low-temperature reservoir?
As long as the related high-temperature reservoir is at a temperature above 700 K and heat is dumped into the 700 K low-temperature reservoir, 700 K is considered to be low-temperature.
55
A system that moves toward a higher state of order also moves toward a lower state of:
entropy.
56
The phrase “heat death of the universe” refers to:
everything in the universe eventually becoming the same temperature
57
Our basic knowledge of the properties of static electricity began in the _ century
Our basic knowledge of the properties of static electricity began in the eighteenth century
58
Static electricity exists when there is an unbalance among the number of
Static electricity exists when there is an unbalance among the number of electrons
59
In his famous experiment of the late 1700s, Charles Coulomb
In his famous experiment of the late 1700s, Charles **Coulomb** **measured the force of the electric charge in objects**
60
Coulomb discovered that the electrical force equation was very similar to the force equation ________ had discovered
Coulomb discovered that the electrical force equation was very similar to the force equation **Sir Isaac Newton** had discovered
61
In what way does Newton's law of universal gravitation differ from Coulomb's law?
(a) Electrical forces can be either attractive or repulsive, while gravity is only attractive.
(b) Only Newton's law of gravity requires a universal constant.
(c) Only Coulomb's law addresses distance in describing the effect of one object on another. (d) Newton's law required experimentation but Coulomb's law did not.
(e) Newton's and Coulomb's laws are really identical, so there is no significant difference
In what way does Newton's law of universal gravitation differ from Coulomb's law?
(a) Electrical forces can be either attractive or repulsive, while gravity is only attractive.
62
How is the force of two charged particles related to their charges?
(a) proportional to the product of their charges divided by the cube of the distance between them
(b) proportional to the product of their charges divided by the square of the distance between them
(c) proportional to the ratio of their charges divided by the distance between them
(d) proportional to the ratio of their charges multiplied by the square of the distance between them
(e) No known relation exists between charged particles and force
How is the force of two charged particles related to their charges?
(b) proportional to the product of their charges divided by the square of the distance between them
63
Coulomb's law states that force is dependent on
(a) the Coulomb constant.
(b) the sizes of the two objects.
(c) the charge of the smaller object.
(d) the distance between the two objects.
(e) the charge of the larger object
Coulomb's law states that force is dependent on
(a) the Coulomb constant.
(c) the charge of the smaller object.
(d) the distance between the two objects.
(e) the charge of the larger object
64
The lines of force radiating from a charged object is called a/an:
electrical field.
65
What are some ways the Earth's magnetic field is or was used for navigation?
(a) Sailors of the past used compasses to direct their course.
(b) Some bacteria navigate up and down within pond ooze.
(c) Some migratory birds are directed by the magnetic field.
(d) The Australian silvereye can see the magnetic fields using a form of color vision.
(e) All of the choices are ways in which the magnetic field is or was used for navigation.
What are some ways the Earth's magnetic field is or was used for navigation?
(a) Sailors of the past used compasses to direct their course.
(b) Some bacteria navigate up and down within pond ooze.
(c) Some migratory birds are directed by the magnetic field.
(d) The Australian silvereye can see the magnetic fields using a form of color vision.
66
William Gilbert discovered many important properties of magnets. Which of the following are among Gilbert's findings?
(a) Every magnet has at least two poles.
(b) If magnetic poles are alike they repel each other.
(c) Steel rods can be magnetized by stroking them with a lodestone.
(d) Electric currents can be produced by changing magnetic fields.
(e) Iron's magnetism can be destroyed by heating.
**Gilbert**
(a) Every magnet has at least two poles.
(b) If magnetic poles are alike they repel each other.
(c) Steel rods can be magnetized by stroking them with a lodestone.
(e) Iron's magnetism can be destroyed by heating.
67
The south pole of the magnetic field of the Earth is located near
The south pole of the magnetic field of the Earth is located near the north pole
68
Every electrical circuit contains an __ flow path.
Every electrical circuit contains an unbroken flow path.
69
One amp of electrical current is equal to
one coulomb of charge per second
70
Which of the following items would use only low-resistance wires
(a) a toaster
(b) a space heater (electric heater for a room in your house)
(c) an electrical transmission line
(d) an incandescent light bulb
(e) a hair dryer
(c) an electrical transmission line
71
Ohm's Law equation
voltage (volts) = current (amps) x resistance (ohms).
72
Approximately how much electrical current will flow through a 250-watt stereo system to play a compact disk in the United States?
2 amps
73
Approximately how much power is consumed per hour by an electric stove drawing 40 amps? (Note - This electric stove is plugged into a 240 volt wall socket.)
9.6 kilowatts/hour
74
In a series circuit, the loads are linked by:
a single wire
75
moving __ can produce magnetic fields
moving electrical charges can produce magnetic fields
76
The functioning of an electric motor depends on the fact that
The functioning of an electric motor depends on the fact that an electrical current produces a magnetic field
77
To achieve a negative charge, you would most likely do what?
Add electrons to the object
78
The electrical force between two charges has a magnitude of 16 N. If the separation between the charges is doubled, what is the new force acting between them?
4 N
79
What is the word that describes the situation when electrical charges are motionless?
Static
80
When you rub a piece of iron with a magnet, what happens?
The iron becomes magnetic itself.
81
A significant difference between an electric field and a magnetic field is
A magnetic field line has to loop around while an electric field may go off to infinity
82
When electric charges are in motion, we have
When electric charges are in motion, we have an electric current
83
The current through a 5.0 omh resistor is 0.40 A. What is the voltage across the resistor?
2.0 V
84
The unit for electric current is which of the following?
Ampere
85
Which of the following is another way of stating Ohm’s Law?
The current through a circuit increases as the voltage across the circuit increases and as the resistance of the circuit decreases
86
The current in a circuit is 0.5 A and the voltage across it is 12 V. The power being supplied by the source is
6 W
87
If we place a magnet near a current-carrying wire, which of the following can happen?
The magnet may exert a force on the current
88
An electric motor Converts ___ energy to ___ energy and heat
An electric motor Converts electrical energy to mechanical energy and heat
89
A bar magnet is magnetic even when no electric current is passing through it. Why?
Bar magnets take advantage of the electrons moving around in atoms to create a magnetic field.
90
Maxwell’s equations mathematically describe
(a) the relationship between changing _ fields and _ fields.
(b) the relationship between changing _ fields and _ fields.
(c) the relationship between electric fields and _ and magnetic fields and \_
Maxwell’s equations mathematically describe
(a) the relationship between changing electric fields and magnetic fields.
(b) the relationship between changing magnetic fields and electric fields.
(c) the relationship between electric fields and charges and magnetic fields and poles
91
Glaciers are found:
(a) at the South Pole.
(b) in Iceland
(c) in Greenland
(d) in some high mountains
(e) all of the above
Glaciers are found:
(a) at the South Pole.
(b) in Iceland
(c) in Greenland
(d) in some high mountains
92
Substantial groundwater is stored in:
(a) underground lakes and rivers.
(b) Aquifers.
(c) igneous rocks and volcanoes.
(d) all of the above.
Substantial groundwater is stored in:
(b) Aquifers.
93
What is the second largest reservoir of water on earth?
glaciers and ice caps
94
Periodic glaciations are caused by
(a) changes in the tilt of the Earth’s axis.
(b) changes in the shape of the Earth’s orbit.
(c) increased precipitation.
(d) decreased solar energy absorption.
(e) all of the above.
Periodic glaciations are caused by
(a) changes in the tilt of the Earth’s axis.
(b) changes in the shape of the Earth’s orbit.
(c) increased precipitation.
(d) decreased solar energy absorption.
95
The surface currents of the ocean:
(a) carry warm water to the poles.
(b) carry cold water to the equator.
(c) can move water away from a coastline.
(d) are independent of the tides.
(e) all of these are correct
The surface currents of the ocean:
(a) carry warm water to the poles.
(b) carry cold water to the equator.
(c) can move water away from a coastline.
(d) are independent of the tides.
96
The name Milankovitch is associated with:
(a) Global Climate Models (GCMs).
(b) research on greenhouse climate changes.
(c) a theory that the Earth’s climate is affected by its orbit.
(d) research on plate tectonics.
(e) research on both greenhouse climate changes and plate tectonics
The name Milankovitch is associated with:
(c) a theory that the Earth’s climate is affected by its orbit.
97
The ocean is maintaining a constant salinity because:
chemical reactions in the oceans combine elements into compounds that are stored in the biota or ocean sediment.
98
The ocean levels _ during an ice age
The ocean levels drop during an ice age
99
The hydrologic cycle has effect on:
(a) an other of Earth’s cycles
(b) the rock cycle.
(c) the atmospheric cycle.
(d) the chemical cycle.
(e) none of the above
(f) all of the above
The hydrologic cycle has effect on:
(a) an other of Earth’s cycles
(b) the rock cycle.
(c) the atmospheric cycle.
(d) the chemical cycle.
100
With so much water covering the surface of our planet (about 75%), how is it that scientists and planners are concerned about a water shortage?
Less than 1% of Earth’s water is available for human consumption and much of that is - or soon will be - polluted. It is very expensive to take water from other sources like glaciers or the ocean and make it available for human consumption.
101
Briefly explain how the oceans are governing the climate of the world
Circulation in the global ocean is a conveyor that redistributes heat across the surface of the planet, and in doing so determines the climate.
