Question 1

The moons of Saturn named Tethys and Dione have a 2:3 orbital resonance with Tethys orbiting closer to Saturn than Dione.If the semimajor axis of Dione's orbit is 380,000 km,what is the semimajor axis of Tethy's orbit?

Accepted Answer

A)  700,000 km 
B)  570,000 km 
C)  290,000 km 
D)  250,000 km

Question 2

No matter what shape Earth might be,the combined force of gravity from all the pieces of Earth would still pull on you perpendicular to the surface on which you are standing.

Accepted Answer

A) True 
 B)False

Question 3

Chaos means that although one can describe the motion of three or more bodies due to their gravitational interactions with each other,it is not possible to predict their motion exactly over long periods of time.

Accepted Answer

A) True 
 B)False

Question 4

Explain why a person at the center of Earth would be weightless.

Accepted Answer

The answer of Explain why a person at the center...

Question 5

The Moon's tidal forces on Earth result in it pulling the near side of Earth toward it and pushing the far side of Earth away from it.

Accepted Answer

A) True 
 B)False

Question 6

Why does Saturn have rings while Earth does not?

Accepted Answer

A)  Saturn is cooler than Earth. 
B)  Saturn is more massive than Earth. 
C)  Saturn rotates faster than Earth. 
D)  Saturn has a thicker atmosphere than Earth.

Question 7

How much of the Moon's surface can we see from Earth?

Accepted Answer

A)  40 percent 
B)  50 percent 
C)  60 percent 
D)  100 percent

Question 8

Although the Sun's gravitational pull on Earth is nearly 200 times greater than the Moon's,its tidal effect is only about 50 percent of the Moon's tidal effect.

Accepted Answer

A) True 
 B)False

Question 9

When a tiny change in a system's parameters.such as position or speed,can develop into large differences in later motion or behavior,the system is called

Accepted Answer

A)  unpredictable. 
B)  chaotic. 
C)  quantum mechanical. 
D)  deterministic.

Question 10

Orbital resonances produce gaps in Saturn's rings.

Accepted Answer

A) True 
 B)False

Question 11

If high tide occurred at  .today,when will high tide occur tomorrow afternoon?

Accepted Answer

A)  12:00 noon 
B)  11:00 A.M. 
C)  11:30 A.M. 
D)  12:30 P.M.

Question 12

Consider a particle inside the Earth located a distance of one-third the Earth's radius  from the center of the Earth.Assuming the Earth has a uniform density,how would the gravitational force on that particle compare to the gravitational force it would experience at the Earth's surface?

Accepted Answer

A)  The gravitational force at one-third  would be 3 times smaller than at the Earth's surface. 
B)  The gravitational force at one-third  would be 3 times larger than at the Earth's surface. 
C)  The gravitational force at one-third  would be 9 times smaller than at the Earth's surface. 
D)  The gravitational force at one-third  would be 9 times larger than at the Earth's surface.

Question 13

If you arrive at the beach and see that the Moon is 45 degrees above the western horizon,you know that

Accepted Answer

A)  high tide will occur in about six hours. 
B)  low tide will occur in about six hours. 
C)  low tide occurred three hours ago. 
D)  high tide occurred three hours ago.

Question 14

Because of libration,we can see over 50 percent of the Moon's surface from Earth.

Accepted Answer

A) True 
 B)False

Question 15

Jupiter's tidal force on its moon Europa is thought to keep Europa's interior hot enough for liquid oceans to exist under its icy surface.How much larger is the tidal force of Jupiter on Europa compared to that of the Earth on the Moon? Europa has a semimajor axis that is 1.7 times the Moon's semimajor axis,and a mass that is 0.7 times that of the Moon.The diameter of Jupiter is 11 times that of the Earth,and the mass of Jupiter is 320 times that of the Earth.

Accepted Answer

The answer of Jupiter's tidal force on its moon Europa...

Question 16

How many Lagrange equilibrium points are there around a planet that orbits the Sun,approximately where are they located (draw a diagram),and why are they important?

Accepted Answer

The answer of How many Lagrange equilibrium points are there...

Question 17

If a moon is asymmetric,but it has a circular orbit around a planet,over time

Accepted Answer

A)  its orbit will become more elliptical. 
B)  its orbit will decay and the moon eventually will be torn apart. 
C)  its rotation rate will become equal to its orbital period. 
D)  its rotation rate will increase.

Question 18

Tides cause the poles of Earth to be pulled closer to each other than they would otherwise be.

Accepted Answer

A) True 
 B)False

Question 19

In a three body system,gravity controls the motion of each of the objects,

Accepted Answer

A)  and their future positions can be predicted accurately at any time in the future. 
B)  and their future positions can be predicted accurately at any time in the past. 
C)  but we cannot predict their positions far into the future because of friction. 
D)  but we cannot accurately predict their positions far into the future due to chaos.

Question 20

Ocean tides on Earth are caused only by the Moon.

Accepted Answer

A) True 
 B)False

Exam 10: Gravity Is More Than Keplers Laws

The moons of Saturn named Tethys and Dione have a 2:3 orbital resonance with Tethys orbiting closer to Saturn than Dione.If the semimajor axis of Dione's orbit is 380,000 km,what is the semimajor axis of Tethy's orbit?

No matter what shape Earth might be,the combined force of gravity from all the pieces of Earth would still pull on you perpendicular to the surface on which you are standing.

Chaos means that although one can describe the motion of three or more bodies due to their gravitational interactions with each other,it is not possible to predict their motion exactly over long periods of time.

Explain why a person at the center of Earth would be weightless.

The Moon's tidal forces on Earth result in it pulling the near side of Earth toward it and pushing the far side of Earth away from it.

Why does Saturn have rings while Earth does not?

How much of the Moon's surface can we see from Earth?

Although the Sun's gravitational pull on Earth is nearly 200 times greater than the Moon's,its tidal effect is only about 50 percent of the Moon's tidal effect.

When a tiny change in a system's parameters.such as position or speed,can develop into large differences in later motion or behavior,the system is called

Orbital resonances produce gaps in Saturn's rings.

If high tide occurred at .today,when will high tide occur tomorrow afternoon?

Consider a particle inside the Earth located a distance of one-third the Earth's radius from the center of the Earth.Assuming the Earth has a uniform density,how would the gravitational force on that particle compare to the gravitational force it would experience at the Earth's surface?

If you arrive at the beach and see that the Moon is 45 degrees above the western horizon,you know that

Because of libration,we can see over 50 percent of the Moon's surface from Earth.

How many Lagrange equilibrium points are there around a planet that orbits the Sun,approximately where are they located (draw a diagram),and why are they important?

If a moon is asymmetric,but it has a circular orbit around a planet,over time

Tides cause the poles of Earth to be pulled closer to each other than they would otherwise be.

In a three body system,gravity controls the motion of each of the objects,

Ocean tides on Earth are caused only by the Moon.