history of the universe exam 2
einstein's theory, like Newton's, predicts that, in the absence of air resistance, all objects should fall at the same rate regardless of their masses. Consider the following hypothetical experimental results. Which one would indicate a failure of Einstein's theory? A. Scientists dropping balls from the Leaning Tower of Pisa find that balls of different mass but the same size fall at slightly different rates. B. Scientists dropping balls from the Leaning Tower of Pisa find that balls of different size but the same mass fall at slightly different rates. C. Scientists dropping balls on the Moon find that balls of different mass fall at slightly different rates.
C. Scientists dropping balls on the Mood find that balls of different mass fall at slightly different rates.
compared to its angular momentum when it is farthest from the Sun, Earth's angular momentum when it is nearest to the Sun is A. Greater. B. Less. C. The same.
C. The same.
which of the following forms of light can be observed with telescopes at sea level? Select all that apply. A. X-rays B. Ultraviolet light C. Visible light D. Infrared light E. Radio waves
C. Visible Light E. Radio Waves
which of the following statements about X-rays and radio waves is not true? A. X-rays and radio waves are both forms of light, or electromagnetic radiation. B. X-rays have shorter wavelengths than radio waves. C. X-rays travel through space faster than radio waves. D. X-rays have higher frequency than radio waves.
C. X-rays travel through space faster than radio waves.
when we say that a planet has a highly eccentric orbit, we mean that: A. It is spiraling in toward the Sun. B. Its orbit is an ellipse with the Sun at one focus. C. In some parts of its orbit it is much closer to the Sun than in other parts.
C. in some parts of its orbit it is much closer to the Sun than in other parts.
"a huge fleet of alien spacecraft will land on Earth and introduce an era of peace and prosperity on January 1, 2035." A. This claim can be evaluated scientifically by predicting whether the aliens will introduce an era of peace and prosperity. B. The claim can't be evaluated scientifically as we do not know the true purpose of the aliens arriving. C. The claim can't be evaluated scientifically as we do not whether the aliens will arrive on Earth on the appointed date. D. The claim can be evaluated scientifically by seeing whether or not the aliens show up on the appointed date.
D. The claim can be evaluated by seeing whether or not the aliens show up on the appointed date.
as a comet orbits around the Sun, its maximum speed is twice its minimum speed. What can we say about its orbit? A. The orbit is nearly circular. B. The eccentricity of the orbit must be over 0.95. C. The orbit cannot be an elipse. D. The comet is twice as far from the Sun at aphelion as at perihelion.
D. The comet is twice as far from the Sun at aphelion as at perihelion.
absolute zero on the Celsius temperature scale is -273.15 °C. what is absolute zero on the Fahrenheit temperature scale? A. -331.67 °F B. -363.67 °F C. -395.67 °F D. -427.67 °F E. -459.67 °F
E. -459.67
the speed of sound in a certain metal block is 3.00 x 103 m/s. the graph shows the amplitude (in meters) of a wave traveling through the block versus time (in milliseconds). what is the wavelength of this wave? A. 0.5 m B. 1.5 m C. 3.0 m D. 4.0 m E. 6.0 m
E. 6.0
from lowest energy to highest energy, which of the following correctly orders the different categories of electromagnetic radiation? A. Visible light, infrared, X-rays, ultraviolet, gamma rays, radio B. Infrared, visible light, ultraviolet, X-rays, gamma rays, radio C. Radio, X-rays, visible light, ultraviolet, infrared, gamma rays D. Gamma rays, X-rays, visible light, ultraviolet, infrared, radio E. Radio, infrared, visible light, ultraviolet, X-rays, gamma rays
E. Radio, infrared, visible light, ultraviolet, x-rays, gamma rays.
if you have a telescope that is observing light with wavelengths of a few meters, you are observing __________. A. Ultraviolet light B. X-rays C. Gamma rays D. Infrared light E. Visible light F. Radio waves
F. Radio waves
x-ray photons have a _____ wavelength, _____ frequency, and _____ energy than do ultraviolet photons. A. Shorter, higher, lower B. Longer, lower, higher C. Shorter, lower, higher D. Longer, lower, lower E. Longer, higher, higher F. Shorter, higher, higher
F. Shorter, higher, higher.
what is its average distance (semimajor axis) from the Sun? Express your answer using three significant figures.
a = 67.7 AU
Kepler's second law of planetary motion
a planet moves faster in the part of its orbit nearer the Sun and slower when farther from the Sun, sweeping out equal areas in equal times.
two fans are watching a baseball game from different positions. One fan is located directly behind home plate, 18.3 m from the batter. The other fan is located in the centerfield bleachers, 127 m from the batter. Both fans observe the batter strike the ball at the same time, but the fan behind home plate hears the sound first. What is the time difference between hearing the sound at the two locations? Use 345 m/s as the speed of sound. A. 0.316 s B. 0.368 s C. 3.17 s D. 1.89 s E. 0.053 s
A. 0.316 s
how far does the planet in part F orbit from the Sun? A. 10 AU B. 100 AU C. √1000 AU D. 1000 AU
A. 10 AU
the acceleration of gravity on Earth is approximately 10 m/s2 (more precisely, 9.8 m/s2). If you drop a rock from a tall building, about how fast will it be falling after 3 seconds? A. 30 m/s B. 10 m/s C. 10 m/s^2 D. 20 m/s E. 30 m/s^2
A. 30 m/s
approximately how fast is Jupiter orbiting the Sun? A. a little less than 15 km/s B. 10 km/s C. 20 km/s D. cannot be determined from the information provided
A. A little less than 15 km/s
an asteroid with an average orbital distance of 2 AU will orbit the Sun at an average speed that is __________. A. A little slower than the orbital speed of Mars B. A little faster than the orbital speed of Mars C. The same as the orbital speed of Mars
A. A little slower than the orbital speed of Mars
considering Einstein's equation relating mass and energy, E = mc2, which of the following statements is true? A. A small amount of mass can be turned into a large amount of energy. B. One kilogram of mass represents 1 joule of energy. C. It takes a large amount of mass to produce a small amount of energy. D. You can make mass into energy if you can accelerate the mass to the speed of light. E. Mass can be turned into energy, but energy cannot be turned back into mass.
A. A small amount of mass can be turned into a large amount of energy.
if you actually performed and compared the two trials chosen in Part C, you would find that, while the basketball and marble would hit the ground at almost the same time, it would not quite be exact: The basketball would take slightly longer to fall to the ground than the marble. Why? A. Because air resistance has a greater effect on the larger ball. B. Because gravity has a greater effect on the larger ball. C. Because gravity has a greater effect on the smaller ball. D. Because air resistance has a greater effect on the smaller ball.
A. Because air resistance has a greater effect on the larger ball.
how does a rocket launch upwards? Choose the statement that best describes why a rocket goes up. A. By expelling gas downwards, the rocket is propelled upwards. B. By expelling gas, the rocket loses mass; because it is lighter, it rises up. C. By expelling gas downwards, which pushes against the ground, the rocket is propelled upwards.
A. By expelling gas downwards, the rocket is propelled upwards.
suppose two comets, comet A and comet B, were orbiting the Sun, having the same average orbital radii. If comet A had a higher eccentricity than comet B, which comet would, during some portion of its orbit, have the highest orbital speed? A. Comet A. B. Comet B. C. Both comets would have the same highest speed.
A. Comet A
according to the universal law of gravitation, if you triple the distance between two objects, then the gravitational force between them _________. A. Decreases by a factor of 9 B. Increases by a factor of 3 C. Increases by a factor of 9 D. Decreases by a factor of 3
A. Decreases by a factor of 9.
the James Webb Space Telescope is designed primarily to observe __________. A. Infrared light B. Light of all wavelengths C. Visible light D. X-rays E. Gamma rays
A. Infrared Light
if an astronomer claims to have discovered an object with a very eccentric orbit, which of the following best describes the orbital trajectory of the object? A. It looks like a very squashed oval. B. It is circular. C. It looks like a figure 8. D. None of the above.
A. It looks like a very squashed oval.
which of the following was not a major advantage of Copernicus's Sun-centered model over the Ptolemaic model? A. It made significantly better predictions of planetary positions in our sky. B. It offered a more natural explanation for the apparent retrograde motion of planets in our sky. C. It allowed calculation of the orbital periods and distances of the planets.
A. It made significantly better predictions of planetary positions in our sky.
a planet is discovered orbiting the star 51 Peg with a period of four days (0.01 years). 51 Peg has the same mass as the Sun. Mercury's orbital period is 0.24 years, and Venus's is 0.62 years. The average orbital radius of this planet is A. Less than Mercury's. B. Between Mercury's and Venus's. C. Greater than Venus's.
A. Less than Mercury's
the fact that Voyager 1 continues to speed out of the solar system, even though its rockets have no fuel, is an example of A. Newton's first law of motion. B. Newton's second law of motion. C. Newton's third law of motion. D. The universal law of gravitation. E. None of the above
A. Newton's first law of motion.
the fact that Voyager 1 continues to speed out of the solar system, even though its rockets have no fuel, is an example of A. Newton's first law of motion. B. Newton's second law of motion. C. Newton's third law of motion.the universal law of gravitation. D. none of the above
A. Newtons first law of motion
compared to microwave radiation, infrared radiation A. Has shorter wavelengths and higher energy. B. Has longer wavelengths and lower energy. C. Is neither felt nor absorbed by our skin. D. Has longer wavelengths and faster velocity. E. Is detected by all living things.
A. Shorter wavelengths and higher energy
which wave is purely longitudinal? A. Sound Waves in Air B. Radio Waves Traveling Through Air C. Light Waves Traveling Through Vacuum D. Waves on a Plucked Guitar String E. Surface Waves in a Shallow Pan of Water
A. Sound waves in air
which is an essential quality of an accepted scientific result? A. Testability B. Mathematical elegance C. Support by many scientists D. Agreement with previous models
A. Testability
kepler's third law is often stated as p2=a3. The value a3 for a planet is shown on __________. A. The horizontal axis of Figure 1 B. The vertical axis of Figure 1 C. The horizontal axis of Figure 2 D. The vertical axis of Figure 2
A. The horizontal axis of Figure 1.
which statement 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. a & b E. a & b & c
B. Every isolated system becomes more disordered with time.
the gravitational potential energy of a contracting interstellar cloud A. Stays the same at all times. B. Gradually transforms into other forms of energy. C. Gradually grows larger.
B. Gradually transforms into other forms of energy.
as an interstellar cloud of hydrogen gas shrinks in size, its rate of rotation A. Decreases, because its angular momentum is conserved. B. Increases, because its angular momentum is conserved. C. Increases, because its total energy is conserved. D. Decreases, because the force of gravity strengthens as the cloud shrinks. E. Increases, because the force of gravity strengthens as the cloud shrinks.
B. Increases, because its angular momentum is conserved.
when an electron drops to a lower energy level in an atom, A. The atom moves more slowly. B. Light at a wavelength specific to the change in energy levels is emitted. C. The extra energy disappears. D. The electron becomes more massive.
B. Light at a wavelength specific to the change in energy levels is emitted.
suppose that you had "X-ray vision" that allowed you to see X rays. What would you notice when you looked at a friend standing near you that you could not notice with your visible light vision alone? A. You could see your friend's internal muscles but not bones. B. Nothing C. You could see your friend's internal bone structure
B. Nothing
two planets are observed going around a star. Planet Xoron has an orbital period that is twice as long as planet Krypton. Which planet has a shorter average orbital radius? A. Planet Xoron B. Planet Krypton C. Both planets have the same average orbital radius. D. There's not enough information to determine.
B. Planet Krypton
the principal difference between radio waves and visible light is A. Radio waves travel at the speed of sound. B. Radio waves carry substantially more energy per photon. C. Radio waves have a longer wavelength than visible light. D. Only visible light can travel through the vacuum of space. E. Blackbodies cannot produce radio waves.
B. Radio waves carry substantially more energy per photon.
which of the following is not true about scientific progress? A. Science progresses through the creation and testing of models of nature. B. Science advances only through the scientific method. C. Science avoids explanations that invoke the supernatural.
B. Science advances only through the scientific method.
Newton's first law of motion
an object moves at constant velocity if there is no net force acting upon it.
Newton's third law of motion
for any force, there is an equal and opposite reaction force.
Newton's Second Law of Motion
force = mass x acceleration
an asteroid that is moving farther from the Sun is gaining ____________ energy.
gravitational potential energy
rapidly moving comets have more __________ energy than slowly moving ones.
kinetic energy
nuclear fusion in stars converts some of the ________ energy of hydrogen nuclei into light and heat.
mass-energy
Kepler's third law of planetary motion
more distant planets orbit the Sun at slower average speeds, obeying the precise mathematical relationship p2 =a3.
an apple contains chemical energy that your body can convert into other forms energy.
potential energy
the light from Polaris travels through space in the form of _________ energy.
radiative energy
You discover a planet orbiting a distant star that has about the same mass as the Sun, with an orbital period of 95 days. What is the planet's orbital distance? Express your answer using two significant figures.
rplanet = 0.41 AU
Kepler's first law of planetary motion
the orbit of each planet about the Sun is an ellipse with the Sun at one focus.
Due to its much higher density, water heated to 80 degrees (Celsius) contains more ____________ energy than air at the same temperature.
thermal energy
the sun continuously radiates energy into space, some of which is intercepted by the earth. The average temperature of the surface of the earth remains about 300 K. Why doesn't the earth's temperature rise as it intercepts the sun's energy? A. The earth reflects the sun's light. B. The earth radiates an amount of energy into space equal to the amount it receives. C. The energy only raises the temperature of the upper atmosphere and never reaches the surface. D. The thermal conductivity of the earth is low. E. The heat is carried away from the earth by convection currents.
B. The Earth radiates an amount of energy into space equal to the amount it receives.
suppose the Sun were suddenly to shrink in size but that its mass remained the same. According to the law of conservation of angular momentum, what would happen? A. The Sun's rate of rotation would slow. B. The Sun would rotate faster than it does now. C. The Sun's angular size in our sky would stay the same. D. This could never happen, because it is impossible for an object to shrink in size without an outside torque
B. The Sun would rotate faster than it does now.
on (Figure 1), you can see Kepler's third law (p2=a3) from the fact that __________. A. The planet names are labeled on the graph B. The data fall on a straight line C. The axes are labeled with values for p2 and a3
B. The data fall on a straight line.
the amount of gravitational potential energy released as an object falls depends on A. Neither the distance it falls nor its speed at the time it begins falling. B. The distance it falls and its speed at the time it begins falling. C. The distance it falls. D. Its speed at the time it begins falling.
B. The distance it falls and speed at the time it beings falling.
in the Greek geocentric model, the retrograde motion of a planet occurs when: A. Earth is about to pass the planet in its orbit around the Sun. B. The planet actually goes backward in its orbit around Earth. C. The planet is aligned with the Moon in our sky.
B. The planet actually goes backward in its orbit around Earth.
as a comet passes by on its closest approach to the Sun, what can we say about how the sum of its potential and kinetic energy has changed since it was at its maximum distance? A. The sum has decreased. B. The sum has not changed. C. The sum has increased. D. The sum is equal to the universal gravitational constant.
B. The sum has not changed.
suppose you want to know the chemical composition of a distant star. Which piece of information is most useful to you? A. The peak energy of the star's thermal radiation. B. The wavelengths of spectral lines in the star's spectrum. C. Whether the star's spectrum has more emission lines or more absorption lines. D. The Doppler shift of the star's spectrum
B. The wavelengths of spectral lines in the star's spectrum.
if Earth's orbit were very eccentric, but the average distance from the Sun were still 1 AU, its orbital period A. Would be less than one year B. Would still be one year. C. Would be longer than one year.
B. Would still be one year
how did Brownian motion provide evidence for the existence of atoms? Your answer must be clear and concise to get full credit.
Brownian motion is a theory of the irregular jerky motion of tiny particles, and it provides evidence for the existence of atoms because it explains how the tiny dust and grain particles move in an irregular jerky way and how the atoms co-exist together.
the relationship between the atomic theories of Dalton and Democritus is A. Both were based on observations in nature. B. Neither was based on observations in nature. C. Dalton's theory depended upon observation; Democritus's theory did not. D. Democritus's theory depended upon observation; Dalton's theory did not. E. Dalton used the term atom; Democritus did not.
C. Dalton's theory depended upon observation; Democritus's theory did not.
according to the universal law of gravitation, if you triple the distance between two objects, then the gravitational force between them _________. A. Increases by a factor of 9 B. Increases by a factor of 3 C. Decreases by a factor of 9 D. Decreases by a factor of 3
C. Decreases by a factor of 9.
bats navigate by emitting high pitched sound waves and A. Scattering all objects in their path. B. Attracting insects toward the sound. C. Listening for an echo. D. Calculating wave crests per second. E. None of the above
C. Listening for an echo
galileo's contribution to astronomy included: A. Discovering the laws of planetary motion. B. Discovering the law of gravity. C. Making observations and conducting experiments that dispelled scientific objections to the Sun-centered model.
C. Making observations and conducting experiments that dispelled scientific objections to the Sun-centered model.
changing the orbit of a spacecraft by firing thrusters is an example of A. Newton's first law of motion. B. Newton's second law of motion. C. Newton's third law of motion. D. The universal law of gravitation.none of the above
C. Newton's third law of motion
complete the following statement: Most of the heat that is lost to space from the earth occurs by A. Conduction. B. Convection. C. Radiation. D. Both conduction and radiation. E. Both conduction and convection.
C. Radiation
considering Einstein's equation relating mass and energy, E = mc2, which of the following statements is true? A. Mass can be turned into energy, but energy cannot be turned back into mass. B. A small amount of mass can be turned into a large amount of energy. C. You can make mass into energy if you can accelerate the mass to the speed of light. D. It takes a large amount of mass to produce a small amount of energy. E. One kilogram of mass represents 1 joule of energy.
B. A small amount of mass can be turned into a large amount of energy.
why do the planets orbit the Sun (i.e. why don't they crash into the Sun)? A. There is no gravity in space. B. Although the planets experience a force of gravity from the Sun, since they are moving, their trajectories bend around the Sun rather than lead directly into the Sun. C. All astronomical objects move in circular orbits.
B. Although the planets experience a force of gravity from the Sun, since they are moving, their trajectories bend around the Sun rather than lead directly into the Sun.
the shimmer of a hot road in the summer is caused by A. Radiation. B. Convection Currents. C. Entropy. D. The Greenhouse Effect. E. Conduction
B. Convection Currents
the Doppler effect A. Is used by birds to navigate at night. B. Describes sound wave frequency from a moving source. C. Describes sound wave frequency from a resting source. D. Is used to interpret the electromagnetic spectrum. E. Describes light wave refraction through a prism.
B. Describe sound wave and frequency from a moving source.
earth is closer to the Sun in January than in July. Therefore, in accord with Kepler's second law: A. Earth travels faster in its orbit around the Sun in July than in January B. Earth travels faster in its orbit around the Sun in January than in July. C. It is summer in January and winter in July.
B. Earth travels faster in its orbit around the Sun in January than in July.
only one of the statements below uses the term theory in its correct, scientific sense. Which one? A. I have a new theory about the cause of earthquakes, and I plan to start testing it soon. B. Einstein's theory of relativity has been tested and corroborated thousands of times. C. Evolution is only a theory, so there's no reason to think it really happened. D. I wrote a theory that is 152 pages long.
B. Einstein's theory of relativity has been tested and corroborated thousands of times.
how does its average distance compare to that of Pluto? A. Pluto orbits farther than Eris. B. Eris orbits farther than Pluto.
B. Eris orbits farther than Pluto.
suppose (Figure 1) showed a planet on the red line directly above a value of 1000 AU3 along the horizontal axis. On the vertical axis, this planet would be at __________. A. 100 years B. √1000 years^2 C. 1000 years^2 D. 1000^2 years^2
C. 1000 years^2
during an evening news broadcast in Helsinki, Finland, the meteorologist indicated that the day's lowest temperature was -4.0 °C. what is the corresponding value of this temperature on the Fahrenheit scale? A. -7.2 °F B. -4.0 °F C. 17 °F D. 25 °F E. 39 °F
C. 17
an atom of the element gold has an atomic number of 79 and an atomic mass number of 197. If it is neutral, how many protons, neutrons, and electrons does it have? A. 118 protons, 79 neutrons, 118 electrons79 protons, 118 neutrons, 39 electrons B. 118 protons, 39 neutrons, 118 electrons C. 79 protons, 118 neutrons, 79 electrons D. 79 protons, 118 neutrons, 118 electrons
C. 79 protons, 118 neutrons, 79 electrons.
which one of the following is not an example of convection? A. Smoke rises above a fire. B. An eagle soars on an updraft of wind. C. A person gets a suntan on a beach. D. Spaghetti is cooked in water. E. An electric heater warms a room.
C. A person gets a suntan on a beach
which of the following is not true about a scientific theory? A. A theory must explain a wide range of observations or experiments. B. Even the strongest theories can never be proved true beyond all doubt. C. A theory is essentially an educated guess.
C. A theory is essentially an educated guess.
assume you have completed the two trials chosen in Part A. Which of the following possible outcomes from the trials would support Newton's theory of gravity? Neglect effects of air resistance. A. The two balls take different amounts of time to reach the ground. B. The less massive ball takes longer to reach the ground. C. Both balls fall to the ground in the same amount of time. D. The more massive ball takes longer to reach the ground.
C. Both balls fall to the ground in the same amount of time.
tycho brahe's contribution to astronomy included: A. Inventing the telescope. B. Proving that Earth orbits the Sun. C. Collecting data that enabled Kepler to discover the laws of planetary motion.
C. Collecting data that enabled Kepler to discover the laws of planetary motion.
the Moon takes roughly 28 days to complete one orbit around Earth. If the orbital radius of the Moon were twice its actual value, its orbital period would be A. Less than 28 days. B. Roughly 28 days. C. Roughly 56 days. D. More than 56 days.
D. More than 56 days.
uranus, not shown on the graph, orbits about 19 AU from the Sun. Based on the graph, its approximate orbital speed is between about __________. A. 20 and 25 km/s B. 15 and 20 km/s C. 10 and 15 km/s D. 5 and 10 km/s
D. 5 and 10 km/s
which statement about heat and temperature is true? A. Heat and temperature are synonymous to scientists. B. A liter of boiling water and a milliliter of boiling water contain the same amount of heat energy. C. The larger the temperature difference between two objects, the more slowly heat energy will be transferred from one to the other. D. A liter of boiling water and a milliliter of boiling water are the same temperature. E. Two statements above are correct.
D. A liter of boiling water and a milliliter of boiling water are the same temperature.
when an electron in an atom goes from a lower energy state to a higher energy state, the atom can A. Emit a photon of any frequency. B. Emit a photon of a specific frequency.absorb several photons of a specific frequency. C. Absorb a photon of any frequency. D. Absorb a photon of a specific frequency.
D. Absorb a photon of a specific frequency.
at what part of a pot of boiling water would you find the coolest water? A. At the bottom B. In the center C. At the top center D. Along the top sides E. None of the above
D. Along the top sides
if our eyes were sensitive only to X rays, the world would appear __________. A. Gray, black, and white like a medical X ray B. Brighter than normal because X rays carry more energy than visible light photons C. Dark because X-ray light does not reach Earth's surface D. Green, yellow, and orange, because those are the colors of X rays
D. Dark because x-ray light does not reach Earth's Surface.
from shortest to longest wavelength, which of the following correctly orders the different categories of electromagnetic radiation? A. Infrared, visible light, ultraviolet, X-rays, gamma rays, radio. B. Ultraviolet, X-rays, gamma rays, visible light, infrared, radio. C. Radio, infrared, visible light, ultraviolet, X-rays, gamma rays. D. Gamma rays, X-rays, ultraviolet, visible light, infrared, radio
D. Gamma rays, x-rays, ultraviolet, visible light, infrared, radio.
if you had only one telescope and wanted to take both visible-light and ultraviolet pictures of stars, where should you locate your telescope? A. On Earth's surface B. On a tall mountain C. In an airplane D. In space
D. In space
how can an electron in an atom lose energy to go from a higher energy level to a lower energy level? A. It absorbs a photon equal in energy to its own energy drop. B. It exchanges gravitational potential energy for kinetic energy. C. It loses gravitational potential energy. D. It releases a photon equal in energy to its own energy drop. E. It loses kinetic energy.
D. It releases a photon equal in energy to its own energy drop.
how are wavelength, frequency, and energy related for photons of light? A. Longer wavelength means higher frequency and lower energy. B. Longer wavelength means higher frequency and higher energy. C. Longer wavelength means lower frequency and higher energy. D. Longer wavelength means lower frequency and lower energy. E. There is no simple relationship because different photons travel at different speeds
D. Longer wavelength means lower frequency and lower energy.
red light has a _____ wavelength and a _____ frequency than does blue light. A. Shorter, higher B. Longer, higher C. Shorter, lower D. Longer, lower
D. Longer, lower
find Earth's approximate mass from the fact that the Moon orbits Earth in an average time of 27.3 days at an average distance of 384,000 kilometers. (Hint: The Moon's mass is only about 180 of Earth's.) Express your answer to two significant figures and include the appropriate units.
MEarth = 6.0×10^24 kg
Find Jupiter's mass from the fact that its moon Io orbits every 42.5 hours at an average distance of 422,000 kilometers. Express your answer to two significant figures and include the appropriate units.
MJupiter = 1.9×10^27 kg
estimate the mass of the Milky Way Galaxy from the fact that the Sun orbits the galactic center every 230 million years at a distance of 27,000 light-years. (This calculation actually tell us only the mass of the galaxy within the Sun's orbit.) Express your answer using two significant figures.
MMilkyWay = 9.4×10^10 solar masses
Pluto's moon Charon orbits Pluto every 6.4 days with a semimajor axis of 19,700 kilometers. Calculate the combined mass of Pluto and Charon. Express your answer to two significant figures and include the appropriate units.
MPluto+MCharon = 1.5×1022 kg
calculate the orbital period of a spacecraft in an orbit 300 kilometers above Earth's surface. Express your answer using one significant figure.
T = 90 min
entropy is a measure of disorder in a system. The Second Law of Thermodynamics states that the entropy of an isolated system remains constant or increases with time. Present a clear and reasoned argument whether the theory of evolution violates the Second Law. Evolution is the idea that life on Earth gradually evolved from lower forms of life, such as microbes to higher forms of life, such as humans.
The second law of thermodynamics states that the total entropy of an isolated system can never decrease over time, and is constant if and only if all processes are reversible. ... The increase in entropy accounts for the irreversibility of natural processes, and the asymmetry between future and past.
