Question 1

A satellite is orbiting Earth in an elliptical orbit.The distance of the satellite from Earth at the aphelion (rA)is twice that at the perihelion (rB).The total energy (potential and kinetic)of the satellite at A is _____ the total energy at B.

Accepted Answer

A) the same as 
B) twice 
C) half 
D) one quarter 
E) four times

Question 2

The acceleration due to gravity in the vicinity of Earth

Accepted Answer

A) varies directly with the distance from the center of Earth. 
B) is a constant that is independent of altitude. 
C) varies inversely with the distance from the center of Earth. 
D) varies inversely with the square of the distance from the center of Earth. 
E) is described by none of these.

Question 3

Suppose a rocket is fired vertically upward from the surface of Earth with one-half of the escape speed.How far from the center of Earth will it reach before it begins to fall back? (Let g = 9.8 m/s2 and RE = 6370 km.)

Accepted Answer

A) 1.3 $\times$ 104 km 
B) 8.5 $\times$ 103 km 
C) 9.6 $\times$ 103 km 
D) 2.6 $\times$ 104 km 
E) 1.9 $\times$ 104 km

Question 4

NASA trains astronauts in "zero-g" by flying a C-9 jet plane in a parabolic path,the so called "Weightless Wonder" or the "Vomit Comet" flights.One path the plane takes is expressed as y = yo + 0.8 x - 2.18 $\times$ 10-4 x2 where yo is the highest point,and x and y are the horizontal and vertical coordinates (in m).What is the horizontal speed of the plane?

Accepted Answer

A) 50 m/s 
B) 100 m/s 
C) 150 m/s 
D) 200 m/s 
E) 250 m/s

Question 5

When two masses are a distance R apart,each exerts a force of magnitude F on the other.When the distance between them is changed to 4R,the force is changed to

Accepted Answer

A) 16F 
B) 4F 
C) F/2 
D) F/4 
E) F/16

Question 6

What is the difference in the force of gravity on a 1.0-kg mass at the bottom of the deepest ocean trench and that at the top of the highest mountain? Assume that g = 9.8 m/s2 at sea level.The radius of Earth at sea level is 6.37 $\times$106 m.The deepest trench is the Marianas Trench,south of Guam,which has a depth
D = 1.103 $\times$ 104 m below sea level.The highest mountain is Everest in Nepal,which has a height of h = 8.847 $\times$ 103 m above sea level.The difference is

Accepted Answer

A) 0.061 N 
B) 0.0067 N 
C) 0.027 N 
D) 0.034 N 
E) 0.0062 N

Question 7

A rocket is launched straight up from the surface of Earth with a speed v,such that the rocket reaches a maximum height of RE above the surface.Find the launch speed of the rocket.Neglect air resistance.(RE = 6.38 $\times$ 106 m,ME = 5.98 $\times$ 1024 kg,G = 6.67 $\times$ 10-11 N·m2/kg2)

Accepted Answer

A) 2.81 km/s 
B) 5.59 km/s 
C) 11.2 km/s 
D) 7.91 km/s 
E) None of the above

Question 8

The moon has a period of 27.3 d and is an average distance from Earth of 3.84 $\times$ 105km.A communications satellite is placed in an Earth orbit at 4.23 $\times$ 104 km from the center of Earth.What is the period of this satellite?

Accepted Answer

A) 0.87 h 
B) 1.0 d 
C) 3.0 d 
D) 6.3 d 
E) 8.0 h

Question 9

Suppose that a satellite is in a circular orbit at a height of 2.00 $\times$ 106 m above Earth's surface.What is the period of the satellite's motion at this elevation?

Accepted Answer

A) 5.65 h 
B) 4.24 h 
C) 1.07 h 
D) 2.12 h 
E) None of these is correct.

Question 10

The constant of universal gravitation is

Accepted Answer

A) ~9.81 m/s2  
B) ~6.67 $\times$ 10-11 N · m2/kg2  
C) ~the gravitational attraction between the masses of any two bodies. 
D) ~the ratio of the forces of attraction between any two masses. 
E) None of these is correct.

Question 11

In a distant galaxy,a planet orbits its sun at a distance of 1.8 $\times$ 1012 m with a period of 108s.A second planet orbits the same sun at a distance of 9 v 1011 m.What is the period of the second planet?

Accepted Answer

A) 5 $\times$ 107 s 
B) 2 $\times$ 108 s 
C) 0.35 $\times$ 108 s 
D) 2.8 $\times$ 108 s 
E) 5 $\times$ 108 s

Question 12

Use the following scenario to answer the next problem.
NASA's "Weightless Wonder" flights can simulate "zero-g" or some other extraterrestrial gravity by flying a C-9 jet plane in a parabolic path.One path the plane takes is expressed as y = yS1U1B1oS1U1B0 + 0.8x – 1.02 x10S1U1P1-4S1S1P0 xS1U1P12S1S1P0 where yS1U1B1oS1U1B0 is the highest point, and x and y are the horizontal and vertical coordinates (in m). 
-What is the horizontal speed of the plane if the flight is to simulate lunar gravity, gMoon = 1.62 m/s2.

Accepted Answer

A) 50 m/s 
B) 100 m/s 
C) 150 m/s 
D) 200 m/s 
E) 250 m/s

Question 13

During the lunar mission of Apollo 11,Armstrong and Aldrin descended to the moon's surface in the lunar module while Collins remained in orbit in the command module.If the command module's period was 2 hours and 20 minutes,how high above the moon's surface did it orbit? (mmoon = 7.35 $\times$ 1022 kg,Rmoon = 1.74 $\times$ 106 m,and G = 6.67 $\times$10-11 N · m2/kg2.)

Accepted Answer

A) 3.22 $\times$ 105 m 
B) 1.04 $\times$ 1011 m 
C) 5.67 $\times$ 102 m 
D) 2.53 $\times$ 103 m 
E) Not enough information is given to answer this question.

Question 14

Kepler's second law,"a line joining any planet to the Sun sweeps out equal areas in equal times" is based on which conservation principle?

Accepted Answer

A) conservation of energy 
B) conservation of linear momentum 
C) conservation of angular momentum 
D) the work-energy theorem 
E) It is not based on any conservation principle.

Question 15

At the surface of the moon,the acceleration due to the gravity of the moon is  .At a distance from the center of the moon equal to three times the radius of the moon,the acceleration due to the gravity of the moon is

Accepted Answer

A) 9  
B)   /3 
C)   /4 
D)   /9 
E) 27

Question 16

Newton's law of gravity is F = GMm/r2.What are the SI units of the gravitational constant G?

Accepted Answer

A) G has no dimensions 
B) N · kg2/m2  
C) N · m2/kg2  
D) kg2/N · m2  
E) None of these is correct.

Question 17

A planet is made of two distinct materials.From the core to R/2,the density of the material is 4000 kg/m3,and from R/2 to R the density is 3000 kg/m3.What is the gravity at the surface of the planet if R = 5000 km?

Accepted Answer

A) 0.699 m/s2 
B) 3.66 m/s2 
C) 4.19 m/s2 
D) 4.38 m/s2 
E) 4.99 m/s2

Question 18

Suppose that a satellite is in a circular orbit at a height of 2.00 $\times$ 106 m above Earth's surface.What is the acceleration due to gravity at this elevation?

Accepted Answer

A) 9.80 m/s2  
B) 3.22 m/s2  
C) 5.67 m/s2  
D) 7.68 m/s2  
E) None of these is correct.

Question 19

Earth's gravitational field is given by  .The total flux (field times area)for a spherical surface area A that encloses all the field lines is

Accepted Answer

A)  -4$\pi$GME 
B)  -GME 
C)  -GME/4$\pi$ 
D)  -2$\pi$GME 
E)  -4GME

Question 20

The Cavendish experiment has been described in elementary textbooks as "weighing the Earth." In fact,it was designed to measure the

Accepted Answer

A) acceleration due to gravity. 
B) mass of Earth. 
C) period of an Earth satellite. 
D) gravitational constant G. 
E) variation of g with height.

Exam 11: Gravity

A satellite is orbiting Earth in an elliptical orbit.The distance of the satellite from Earth at the aphelion (r_A) is twice that at the perihelion (r_B) .The total energy (potential and kinetic) of the satellite at A is _____ the total energy at B.

The acceleration due to gravity in the vicinity of Earth

Suppose a rocket is fired vertically upward from the surface of Earth with one-half of the escape speed.How far from the center of Earth will it reach before it begins to fall back? (Let g = 9.8 m/s² and R_E = 6370 km.)

When two masses are a distance R apart,each exerts a force of magnitude F on the other.When the distance between them is changed to 4R,the force is changed to

The moon has a period of 27.3 d and is an average distance from Earth of 3.84 $\times$ 10⁵km.A communications satellite is placed in an Earth orbit at 4.23 $\times$ 10⁴ km from the center of Earth.What is the period of this satellite?

Suppose that a satellite is in a circular orbit at a height of 2.00 $\times$ 10⁶ m above Earth's surface.What is the period of the satellite's motion at this elevation?

The constant of universal gravitation is

In a distant galaxy,a planet orbits its sun at a distance of 1.8 $\times$ 10¹² m with a period of 10⁸s.A second planet orbits the same sun at a distance of 9 v 10¹¹ m.What is the period of the second planet?

Kepler's second law,"a line joining any planet to the Sun sweeps out equal areas in equal times" is based on which conservation principle?

At the surface of the moon,the acceleration due to the gravity of the moon is .At a distance from the center of the moon equal to three times the radius of the moon,the acceleration due to the gravity of the moon is

Newton's law of gravity is F = GMm/r².What are the SI units of the gravitational constant G?

A planet is made of two distinct materials.From the core to R/2,the density of the material is 4000 kg/m³,and from R/2 to R the density is 3000 kg/m³.What is the gravity at the surface of the planet if R = 5000 km?

Suppose that a satellite is in a circular orbit at a height of 2.00 $\times$ 10⁶ m above Earth's surface.What is the acceleration due to gravity at this elevation?

The Cavendish experiment has been described in elementary textbooks as "weighing the Earth." In fact,it was designed to measure the

Exam 11: Gravity

A satellite is orbiting Earth in an elliptical orbit.The distance of the satellite from Earth at the aphelion (rA) is twice that at the perihelion (rB) .The total energy (potential and kinetic) of the satellite at A is _____ the total energy at B.

The acceleration due to gravity in the vicinity of Earth

Suppose a rocket is fired vertically upward from the surface of Earth with one-half of the escape speed.How far from the center of Earth will it reach before it begins to fall back? (Let g = 9.8 m/s2 and RE = 6370 km.)

When two masses are a distance R apart,each exerts a force of magnitude F on the other.When the distance between them is changed to 4R,the force is changed to

A rocket is launched straight up from the surface of Earth with a speed v,such that the rocket reaches a maximum height of RE above the surface.Find the launch speed of the rocket.Neglect air resistance.(RE = 6.38 ×\times× 106 m,ME = 5.98 ×\times× 1024 kg,G = 6.67 ×\times× 10-11 N·m2/kg2)

The moon has a period of 27.3 d and is an average distance from Earth of 3.84 ×\times× 105km.A communications satellite is placed in an Earth orbit at 4.23 ×\times× 104 km from the center of Earth.What is the period of this satellite?

Suppose that a satellite is in a circular orbit at a height of 2.00 ×\times× 106 m above Earth's surface.What is the period of the satellite's motion at this elevation?

The constant of universal gravitation is

In a distant galaxy,a planet orbits its sun at a distance of 1.8 ×\times× 1012 m with a period of 108s.A second planet orbits the same sun at a distance of 9 v 1011 m.What is the period of the second planet?

Kepler's second law,"a line joining any planet to the Sun sweeps out equal areas in equal times" is based on which conservation principle?

At the surface of the moon,the acceleration due to the gravity of the moon is .At a distance from the center of the moon equal to three times the radius of the moon,the acceleration due to the gravity of the moon is

Newton's law of gravity is F = GMm/r2.What are the SI units of the gravitational constant G?

A planet is made of two distinct materials.From the core to R/2,the density of the material is 4000 kg/m3,and from R/2 to R the density is 3000 kg/m3.What is the gravity at the surface of the planet if R = 5000 km?

Suppose that a satellite is in a circular orbit at a height of 2.00 ×\times× 106 m above Earth's surface.What is the acceleration due to gravity at this elevation?

Earth's gravitational field is given by .The total flux (field times area) for a spherical surface area A that encloses all the field lines is

The Cavendish experiment has been described in elementary textbooks as "weighing the Earth." In fact,it was designed to measure the

A satellite is orbiting Earth in an elliptical orbit.The distance of the satellite from Earth at the aphelion (r_A) is twice that at the perihelion (r_B) .The total energy (potential and kinetic) of the satellite at A is _____ the total energy at B.

Suppose a rocket is fired vertically upward from the surface of Earth with one-half of the escape speed.How far from the center of Earth will it reach before it begins to fall back? (Let g = 9.8 m/s² and R_E = 6370 km.)

The moon has a period of 27.3 d and is an average distance from Earth of 3.84 $\times$ 10⁵km.A communications satellite is placed in an Earth orbit at 4.23 $\times$ 10⁴ km from the center of Earth.What is the period of this satellite?

Suppose that a satellite is in a circular orbit at a height of 2.00 $\times$ 10⁶ m above Earth's surface.What is the period of the satellite's motion at this elevation?

In a distant galaxy,a planet orbits its sun at a distance of 1.8 $\times$ 10¹² m with a period of 10⁸s.A second planet orbits the same sun at a distance of 9 v 10¹¹ m.What is the period of the second planet?

Newton's law of gravity is F = GMm/r².What are the SI units of the gravitational constant G?

A planet is made of two distinct materials.From the core to R/2,the density of the material is 4000 kg/m³,and from R/2 to R the density is 3000 kg/m³.What is the gravity at the surface of the planet if R = 5000 km?

Suppose that a satellite is in a circular orbit at a height of 2.00 $\times$ 10⁶ m above Earth's surface.What is the acceleration due to gravity at this elevation?