PHY 102 Final Exam GUARANTEED
PASS!!
What is the speed of light? - (ANSWER)Light can travel enormous distances under short periods
of time. It is faster than any other phenomenon. It takes about 8 minutes for light to travel from
the Sun to Earth. The speed of light in a vacuum is c=3x10^8 m/s.
Why is light such an important tool for astronomers? - (ANSWER)Because light is how we learn
about distant objects without travelling there. It is also a measuring took of astronomy. Light is a
wave and a particle.
How are different kinds of light waves arranged in the EM spectrum? - (ANSWER)Light is
arranged on the electromagnetic (EM) spectrum from shortest wavelength (highest energy) to
longest wavelength (lowest energy). The longer the wavelength the safer it is for people to be
around. Gamma rays have the shortest wavelength and are used for cancer radiation. X-Rays are
used for medical examinations. Infrared radiation is used in a TV remote, microwaves are used
in microwave ovens, and the radio waves are used in mobile phones. They are arranged by
frequency.
What is the relationship between frequency, color, wavelength, and energy? - (ANSWER)Color
is how our eyes distinguish frequency. Speed of light equals frequency times wavelength. If
frequency gets big then wavelength gets smaller and vice versa. E=hf means if energy gets larger
so does frequency (because h is a constant). Frequency and wavelength are connected by speed
of light. If you know one of c=f(lambda) then you are able to calculate them all.
What do these equations express? c=f(lambda) and E=hf? - (ANSWER)c=speed of light,
f=frequency, lambda=wavelength, C=f(lambda) is the equation of speed of light. For E=hf,
E=photon's energy, h=Planck's constant (6.67x10^-34 J) and f=frequency, This is the equation
for measuring a photon's energy.
What are the characteristics of a good scientific theory? - (ANSWER)Good science involves
building upon existing knowledge, can be modified when new information is found, has
predictive power, develops step-by-step, is objective, and can be tested and disproved. Scientific
method steps: observe, hypothesize, predict, test, modify, and simplify. It has predictability, it
can be done repeatedly, and should be objective.
What might cause a scientific theory to be changed or abandoned? - (ANSWER)If the theory is
not testable or if it has been disproved numerous times. It would also be abandoned if it is a
pseudoscience which means it is based off of non-developing facts or it is unable to be tested.
What is the difference between a science and a pseudoscience? - (ANSWER)Science is a process
and is testable and falsifiable, while a pseudoscience is usually impossible to disprove and rarely
has new developments. A pseudoscience has no test-ability, therefore it is not a science.
Page 1 of 14
, What units, and what size scales are needed to measure the universe? - (ANSWER)Science is
generally done in the metric system, and different units are used for different measurements?
Why do stars, Sun, Moon and planets all appear to rise and set in our sky? - (ANSWER)Because
of the way the Earth rotates on its axis. Depending on where you are on Earth, the movements of
the stars appear somewhat different.
What is the Celestial Sphere? How is the coordinate system set up? What are some of the major
features on the celestial sphere? - (ANSWER)The celestial sphere is a fixed coordinate system to
model and map the sky: an imaginary sphere surrounding the Earth in which all objects in the
sky can be located. It has 2 axis points, the north and south celestial poles (located directly above
Earth's poles). There is also a celestial equator (directly above Earth's equator). Longitude is
measured in "right ascension" (in hours), latitude is "declination" (in degrees, minutes, and
seconds), and zero is the celestial equator.
What is the correct explanation for the phases of the Moon? - (ANSWER)The relative angle
between the Sun, Moon, and Earth changes, illuminating the Moon's face differently.
What is the correct explanation for the seasons on Earth? - (ANSWER)Earth's axis is tilted 23.5
degrees with respect to its orbit around the Sun. The tilt changes the seasons.
What is the cause of an eclipse? What kinds of eclipses are there? - (ANSWER)There are lunar
eclipses (when the moon enters the shadow of the Earth). There are 3 types of lunar eclipses.
There is the penumbral eclipse (when the moon enters the penumbra of the Earth's shadow)
which is not very noticeable, a partial eclipse (when the moon is partially in the umbra), and the
moon is half dark, and a total lunar eclipse (when the whole Moon is in the Earth's umbra) and
the moon looks red. There are also solar eclipses (when the moon completely surpasses the sun).
There are partial solar eclipses (when the sun is only partially covered by the moon), and
Annular solar eclipses (when the Moon's umbra falls short of the Earth, the moon appears too
small to cover the Sun), these leave a thin ring, "annulus" of light around the moon.
What is the definition of velocity? How is it related to distance and time? - (ANSWER)Velocity
is defined as "a quantity that specifies both direction and speed of an object." It is related to
distance and time because the equation for velocity is velocity=distance/time, meaning that
distance divided by time make up velocity.
What is the definition of acceleration? How is it related to velocity, distance, and time? -
(ANSWER)A=V/t Acceleration is defined as "a charge in the direction or magnitude of a
velocity." It is related to velocity, distance, and time because the equation for acceleration is
a=(delta) v/t, meaning that acceleration is the change in velocity (and distance factors into
velocity) divided by time.
What does this equation express? v=vo +at - (ANSWER)This equation means: velocity=intial
velocity +constant x time.
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PASS!!
What is the speed of light? - (ANSWER)Light can travel enormous distances under short periods
of time. It is faster than any other phenomenon. It takes about 8 minutes for light to travel from
the Sun to Earth. The speed of light in a vacuum is c=3x10^8 m/s.
Why is light such an important tool for astronomers? - (ANSWER)Because light is how we learn
about distant objects without travelling there. It is also a measuring took of astronomy. Light is a
wave and a particle.
How are different kinds of light waves arranged in the EM spectrum? - (ANSWER)Light is
arranged on the electromagnetic (EM) spectrum from shortest wavelength (highest energy) to
longest wavelength (lowest energy). The longer the wavelength the safer it is for people to be
around. Gamma rays have the shortest wavelength and are used for cancer radiation. X-Rays are
used for medical examinations. Infrared radiation is used in a TV remote, microwaves are used
in microwave ovens, and the radio waves are used in mobile phones. They are arranged by
frequency.
What is the relationship between frequency, color, wavelength, and energy? - (ANSWER)Color
is how our eyes distinguish frequency. Speed of light equals frequency times wavelength. If
frequency gets big then wavelength gets smaller and vice versa. E=hf means if energy gets larger
so does frequency (because h is a constant). Frequency and wavelength are connected by speed
of light. If you know one of c=f(lambda) then you are able to calculate them all.
What do these equations express? c=f(lambda) and E=hf? - (ANSWER)c=speed of light,
f=frequency, lambda=wavelength, C=f(lambda) is the equation of speed of light. For E=hf,
E=photon's energy, h=Planck's constant (6.67x10^-34 J) and f=frequency, This is the equation
for measuring a photon's energy.
What are the characteristics of a good scientific theory? - (ANSWER)Good science involves
building upon existing knowledge, can be modified when new information is found, has
predictive power, develops step-by-step, is objective, and can be tested and disproved. Scientific
method steps: observe, hypothesize, predict, test, modify, and simplify. It has predictability, it
can be done repeatedly, and should be objective.
What might cause a scientific theory to be changed or abandoned? - (ANSWER)If the theory is
not testable or if it has been disproved numerous times. It would also be abandoned if it is a
pseudoscience which means it is based off of non-developing facts or it is unable to be tested.
What is the difference between a science and a pseudoscience? - (ANSWER)Science is a process
and is testable and falsifiable, while a pseudoscience is usually impossible to disprove and rarely
has new developments. A pseudoscience has no test-ability, therefore it is not a science.
Page 1 of 14
, What units, and what size scales are needed to measure the universe? - (ANSWER)Science is
generally done in the metric system, and different units are used for different measurements?
Why do stars, Sun, Moon and planets all appear to rise and set in our sky? - (ANSWER)Because
of the way the Earth rotates on its axis. Depending on where you are on Earth, the movements of
the stars appear somewhat different.
What is the Celestial Sphere? How is the coordinate system set up? What are some of the major
features on the celestial sphere? - (ANSWER)The celestial sphere is a fixed coordinate system to
model and map the sky: an imaginary sphere surrounding the Earth in which all objects in the
sky can be located. It has 2 axis points, the north and south celestial poles (located directly above
Earth's poles). There is also a celestial equator (directly above Earth's equator). Longitude is
measured in "right ascension" (in hours), latitude is "declination" (in degrees, minutes, and
seconds), and zero is the celestial equator.
What is the correct explanation for the phases of the Moon? - (ANSWER)The relative angle
between the Sun, Moon, and Earth changes, illuminating the Moon's face differently.
What is the correct explanation for the seasons on Earth? - (ANSWER)Earth's axis is tilted 23.5
degrees with respect to its orbit around the Sun. The tilt changes the seasons.
What is the cause of an eclipse? What kinds of eclipses are there? - (ANSWER)There are lunar
eclipses (when the moon enters the shadow of the Earth). There are 3 types of lunar eclipses.
There is the penumbral eclipse (when the moon enters the penumbra of the Earth's shadow)
which is not very noticeable, a partial eclipse (when the moon is partially in the umbra), and the
moon is half dark, and a total lunar eclipse (when the whole Moon is in the Earth's umbra) and
the moon looks red. There are also solar eclipses (when the moon completely surpasses the sun).
There are partial solar eclipses (when the sun is only partially covered by the moon), and
Annular solar eclipses (when the Moon's umbra falls short of the Earth, the moon appears too
small to cover the Sun), these leave a thin ring, "annulus" of light around the moon.
What is the definition of velocity? How is it related to distance and time? - (ANSWER)Velocity
is defined as "a quantity that specifies both direction and speed of an object." It is related to
distance and time because the equation for velocity is velocity=distance/time, meaning that
distance divided by time make up velocity.
What is the definition of acceleration? How is it related to velocity, distance, and time? -
(ANSWER)A=V/t Acceleration is defined as "a charge in the direction or magnitude of a
velocity." It is related to velocity, distance, and time because the equation for acceleration is
a=(delta) v/t, meaning that acceleration is the change in velocity (and distance factors into
velocity) divided by time.
What does this equation express? v=vo +at - (ANSWER)This equation means: velocity=intial
velocity +constant x time.
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