ASTRO 7N EXAM 2 2026 EXAM SCRIPT
SOLVED QUESTIONS WITH ACCURATE
SOLUTIONS
◉ Since the jump height is half as high what does that tell us about
gravity? Answer: Twice as much. (More gravity = lower jump height)
◉ Now we can change the mass to 0.5M. If we do, how much higher are
you jumping than at one Earth mass? Answer: Twice as high
◉ Now we can change the mass to 0.25M. If we do, how much higher
are you jumping? Answer: Four times as high
◉ As the mass of the planet increases, the jump height _______ by the
same factor as the mass. Answer: Decreases
◉ Let's keep the mass at Earth's mass but change the radius to half the
radius of the earth. How much higher do you jump? Answer: One-
quarter as high
◉ Let's keep the mass at Earth's mass but change the radius to twice the
radius of earth. How high do you jump? Answer: Four times as high
,◉ Let's keep the mass at Earth's mass but change the radius to three
times the radius of the earth. How high do you jump? Answer: Nine
times as high
◉ As the radius of the planet increases, the jump height _____ as the
square of the radius. Answer: Increases
◉ What is the relationship between gravity, mass and radius? Answer: g
∝ m/r^2
◉ Experiment using Mars' and Earth's gravity to see what effect they
have on gravity. What is its surface gravity compared to Earth? (Mars
has about 1/10 the mass and 1/2 the radius of Earth) Answer: 0.4 times
◉ The Moon has about 1/100 the mass of Earth and about 1/4 the radius.
What is the surface gravity of the Moon compared to earth? Answer:
16/100
◉ Jupiter has about 300 times the mass of Earth and 10 times the radius.
What is the surface gravity of Jupiter compared to Earth? Answer: 3
◉ Saturn has about 100 times the mass of Earth and 10 times the radius.
What is the surface gravity of Saturn compared to Earth? Answer: 1
,◉ Notice that the moon in the panel at the upper right is half
illuminated. Now, how much of the TOTAL surface of the Moon is
illuminated in this phase? Answer: 50%
◉ Now, how much of the TOTAL surface of the moon is illuminated in
the Full Moon phase? Answer: 50% (moon is always illuminated 50%)
◉ What time is it for any observer on Earth when they see the full Moon
rising? Answer: 6PM (Full Moon rises at sunset)
◉ Sunset occurs 6 hours before the Full Moon transits. Now, when does
the Full Moon set? Answer: 6AM (Full Moon sets at sunrise)
◉ When does the Waxing crescent phase (overhead for the green
observer in the picture) RISE? Keep in mind that the Earth is rotating
counter clockwise. Answer: 9AM
◉ When does the Waning Gibbous phase SET? Answer: 9AM
◉ What phase must the moon be in so that an observer on Earth will see
the Moon overhead at 9AM? Answer: Waning Cresent
◉ Where on the sky does the Moon set? Answer: West
, ◉ Both the Moon and the Sun rise and set for the same reason. It is
because of: Answer: the rotation of the Earth
◉ Sun is eclipsed when the Moon is New. That is the only way that is
could block the Sun's light. Is it daytime or nighttime when this occurs?
Answer: Day
◉ What phase is the Moon in during a lunar eclipse? Answer: Full
◉ Is is daytime or nighttime when [the lunar eclipse] occurs? Answer:
Night
◉ We don't see a solar eclipse from Earth every single month. Oh, I see,
the reason is that: Answer: the Moon's orbit around Earth is actually
tipped about 5 degrees to Earth's orbit around the Sun so the Moon isn't
always in the right plane for an eclipse to occur
◉ The inclination [of Phobos] is: Answer: About 1 degree
◉ That means Phobos eclipses: Answer: every orbit
◉ The orbital year [of Phobos] is: Answer: about 8 hours
SOLVED QUESTIONS WITH ACCURATE
SOLUTIONS
◉ Since the jump height is half as high what does that tell us about
gravity? Answer: Twice as much. (More gravity = lower jump height)
◉ Now we can change the mass to 0.5M. If we do, how much higher are
you jumping than at one Earth mass? Answer: Twice as high
◉ Now we can change the mass to 0.25M. If we do, how much higher
are you jumping? Answer: Four times as high
◉ As the mass of the planet increases, the jump height _______ by the
same factor as the mass. Answer: Decreases
◉ Let's keep the mass at Earth's mass but change the radius to half the
radius of the earth. How much higher do you jump? Answer: One-
quarter as high
◉ Let's keep the mass at Earth's mass but change the radius to twice the
radius of earth. How high do you jump? Answer: Four times as high
,◉ Let's keep the mass at Earth's mass but change the radius to three
times the radius of the earth. How high do you jump? Answer: Nine
times as high
◉ As the radius of the planet increases, the jump height _____ as the
square of the radius. Answer: Increases
◉ What is the relationship between gravity, mass and radius? Answer: g
∝ m/r^2
◉ Experiment using Mars' and Earth's gravity to see what effect they
have on gravity. What is its surface gravity compared to Earth? (Mars
has about 1/10 the mass and 1/2 the radius of Earth) Answer: 0.4 times
◉ The Moon has about 1/100 the mass of Earth and about 1/4 the radius.
What is the surface gravity of the Moon compared to earth? Answer:
16/100
◉ Jupiter has about 300 times the mass of Earth and 10 times the radius.
What is the surface gravity of Jupiter compared to Earth? Answer: 3
◉ Saturn has about 100 times the mass of Earth and 10 times the radius.
What is the surface gravity of Saturn compared to Earth? Answer: 1
,◉ Notice that the moon in the panel at the upper right is half
illuminated. Now, how much of the TOTAL surface of the Moon is
illuminated in this phase? Answer: 50%
◉ Now, how much of the TOTAL surface of the moon is illuminated in
the Full Moon phase? Answer: 50% (moon is always illuminated 50%)
◉ What time is it for any observer on Earth when they see the full Moon
rising? Answer: 6PM (Full Moon rises at sunset)
◉ Sunset occurs 6 hours before the Full Moon transits. Now, when does
the Full Moon set? Answer: 6AM (Full Moon sets at sunrise)
◉ When does the Waxing crescent phase (overhead for the green
observer in the picture) RISE? Keep in mind that the Earth is rotating
counter clockwise. Answer: 9AM
◉ When does the Waning Gibbous phase SET? Answer: 9AM
◉ What phase must the moon be in so that an observer on Earth will see
the Moon overhead at 9AM? Answer: Waning Cresent
◉ Where on the sky does the Moon set? Answer: West
, ◉ Both the Moon and the Sun rise and set for the same reason. It is
because of: Answer: the rotation of the Earth
◉ Sun is eclipsed when the Moon is New. That is the only way that is
could block the Sun's light. Is it daytime or nighttime when this occurs?
Answer: Day
◉ What phase is the Moon in during a lunar eclipse? Answer: Full
◉ Is is daytime or nighttime when [the lunar eclipse] occurs? Answer:
Night
◉ We don't see a solar eclipse from Earth every single month. Oh, I see,
the reason is that: Answer: the Moon's orbit around Earth is actually
tipped about 5 degrees to Earth's orbit around the Sun so the Moon isn't
always in the right plane for an eclipse to occur
◉ The inclination [of Phobos] is: Answer: About 1 degree
◉ That means Phobos eclipses: Answer: every orbit
◉ The orbital year [of Phobos] is: Answer: about 8 hours
