Question 1

An astronaut orbits the earth in a space capsule whose height above the earth is equal to the earth's radius.How does the mass of the astronaut in the capsule compare to her mass on the earth?
A)Her mass is equal to her mass on earth.
B)Her mass is approximately equal to one-fourth her mass on earth.
C)Her mass is approximately equal to one-half of her mass on earth.
D)Her mass is approximately equal to one-third of her mass on earth.
E)Her mass is approximately equal to one-sixteenth her mass on earth.

Accepted Answer

The mass of an object does not change with its position or height above the Earth. Therefore, the mass of the astronaut in the capsule remains the same as her mass on Earth.

Question 2

A rock is thrown straight up from the earth's surface.Which one of the following statements concerning the net force acting on the rock at the top of its path is true?
A)The net force is equal to the weight of the rock.
B)The net force is instantaneously equal to zero newtons.
C)The direction of the net force changes from up to down.
D)The net force is greater than the weight of the rock.
E)The net force is less than the weight of the rock, but greater than zero newtons.

Accepted Answer

The answer of A rock is thrown straight up from...

Question 3

Two point masses m and M are separated by a distance d.If the separation d remains fixed and the masses are increased to the values 3m and 3M respectively, how does the gravitational force between them change?
A)The force will be one-third as great.
B)The force will be one-ninth as great.
C)The force will be three times as great.
D)The force will be nine times as great.
E)It is impossible to determine without knowing the numerical values of m, M, and d.

Accepted Answer

According to the Law of Gravitation, the force between two point masses is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.

So, initially the force between the masses is F = GmM/d².

When the masses are increased to 3m and 3M respectively, the force between them becomes F' = G(3m)(3M)/d² = 9(GmM/d²) = 9F.

Therefore, the force between the masses will be nine times as great.

Question 4

A 2.00-kg projectile is fired at an angle of 20.0°.What is the magnitude of the force exerted on the projectile when it is at the highest position in its trajectory? Neglect any effects of air resistance.
A)19.6 N
B)14.7 N
C)9.80 N
D)4.90 N
E)0 N

Accepted Answer

The answer of A 2.00-kg projectile is fired at an...

Question 5

A 70.0-kg astronaut pushes to the left on a spacecraft with a force in "gravity-free" space.The spacecraft has a total mass of 1.0 × 10S1U1P14S1S1P0 kg.During the push, the astronaut accelerates to the right with an acceleration of 0.36 m/sS1U1P12S1S1P0. -Determine the magnitude of the acceleration of the spacecraft. A)51.4 m/s² B)0.36 m/s² C)2.5 × 10^-³ m/s² D)7.0 × 10^-³ m/s² E)3.97 × 10^-⁴ m/s²

Accepted Answer

Since the astronaut is pushing to the left on the spacecraft, the spacecraft will experience a net force to the right. Using Newton's second law, F=ma, we can solve for the acceleration of the spacecraft. F (net) = ma 11eb1913_8dcd_cdc6_b651_f501060c945e_TB3188_11 = (1.0 × 10⁴ kg + 70.0 kg)a Solving for a, we get: a = 2.5 × 10^-³ m/s² Therefore, the magnitude of the acceleration of the spacecraft is 2.5 × 10^-³ m/s².

Question 6

A marble is dropped straight down from a distance h above the floor. Let F_m = the magnitude of the gravitational force on the marble due to the earth; F_e= the magnitude of the gravitational force on the earth due to the marble; A_m= the magnitude of the acceleration of the marble toward the earth; A_e= the magnitude of the acceleration of the earth toward the marble. Which set of conditions is true as the marble falls toward the earth? Neglect any effects of air resistance. A)F_m = F_e and a_m < a_e B)F_m < F_e and a_m > a_e C)F_m < F_e and a_m = a_e D)F_m > F_e and a_m = a_e E)F_m = F_e and a_m > a_e

Accepted Answer

The answer of A marble is dropped straight down from...

Question 7

A horse pulls a cart along a flat road.Consider the following four forces that arise in this situation.
(1) the force of the horse pulling on the cart (3) the force of the horse pushing on the road
(2) the force of the cart pulling on the horse (4) the force of the road pushing on the horse
-Suppose that the horse and cart have started from rest; and as time goes on, their speed increases in the same direction.Which one of the following conclusions is correct concerning the magnitudes of the forces mentioned above?
A)Force 1 exceeds force 2.
B)Force 2 is less than force 3.
C)Force 2 exceeds force 4.
D)Force 3 exceeds force 4.
E)Forces 1 and 2 cannot have equal magnitudes.

Accepted Answer

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Question 8

A physics student in a hot air balloon ascends vertically at constant speed.Consider the following four forces present in this situation: S1U1B11S1U1B0 = the weight of the hot air balloon S1U1B13S1U1B0 = the force of the student pulling on the earth S1U1B12S1U1B0 = the weight of the student S1U1B14S1U1B0 = the force of the hot air balloon pulling on the student -Which one of the following relationships concerning the forces or their magnitudes is true? A)F₄ > F₂ B)F₁< F₂ C)F₄> F₁ D) ₂ = - ₄ E) ₃ = - ₄

Accepted Answer

The answer of A physics student in a hot air...

Question 9

An astronaut orbits the earth in a space capsule whose height above the earth is equal to the earth's radius.How does the weight of the astronaut in the capsule compare to her weight on the earth?
A)Her weight is equal to zero newtons.
B)Her weight is approximately equal to one-fourth her weight on earth.
C)Her weight is approximately equal to one-half of her weight on earth.
D)Her weight is approximately equal to one-third of her weight on earth.
E)Her weight is approximately equal to one-sixteenth her weight on earth.

Accepted Answer

When an object is at a height equal to the radius of the earth, the force of gravity acting on it is only one-fourth of the force of gravity acting on it at the surface of the earth. This means that the weight of the astronaut in the capsule is only one-fourth of her weight on earth. Therefore, the best choice is B.

Question 10

A physics student in a hot air balloon ascends vertically at constant speed.Consider the following four forces present in this situation: S1U1B11S1U1B0 = the weight of the hot air balloon S1U1B13S1U1B0 = the force of the student pulling on the earth S1U1B12S1U1B0 = the weight of the student S1U1B14S1U1B0 = the force of the hot air balloon pulling on the student -Which two forces form an "action-reaction" pair that obeys Newton's third law? A) ₁ and ₂ B) ₂ and ₃ C) ₁ and ₃ D) ₂ and ₄ E) ₃ and ₄

Accepted Answer

The answer of A physics student in a hot air...

Question 11

Consider the following forces. (1) frictional (2) gravitational (3) tension (4) strong nuclear (5) normal (6) electroweak
Which of the forces listed are considered fundamental forces?
A)1, 2, and 4
B)1, 2, 3, and 5
C)1, 3, and 5
D)2, 4, and 6
E)2, 3, 4, and 6

Accepted Answer

The fundamental forces, also known as fundamental interactions, are the four fundamental forces of nature: gravitational, strong nuclear, weak nuclear, and electromagnetic forces. Out of the forces listed, only gravitational (2), strong nuclear (4), and electroweak (6) forces are considered fundamental forces. Therefore, the correct answer is D.

Question 12

What is the weight of a 2.50-kg bag of sand on the surface of the earth?
A)2.50 N
B)9.80 N
C)24.5 N
D)49.0 N
E)98.0 N

Accepted Answer

The answer of What is the weight of a 2.50-kg...

Question 13

A 70.0-kg astronaut pushes to the left on a spacecraft with a force  in "gravity-free" space.The spacecraft has a total mass of 1.0 × 10S1U1P14S1S1P0 kg.During the push, the astronaut accelerates to the right with an acceleration of 0.36 m/sS1U1P12S1S1P0. 
-Which one of the following statements concerning this situation is true?
A)The spacecraft does not move, but the astronaut moves to the right with a constant speed.
B)The astronaut stops moving after he stops pushing on the spacecraft.
C)The force exerted on the astronaut is larger than the force exerted on the spacecraft.
D)The force exerted on the spacecraft is larger than the force exerted on the astronaut.
E)The velocity of the astronaut increases while he is pushing on the spacecraft.

Accepted Answer

The answer of A 70.0-kg astronaut pushes to the left...

Question 14

Which one of the following statements best explains why the weight of an object of mass m is different on Mars than it is on the Earth?
A)The mass of Mars is different from that of Earth.
B)The masses and radii of Mars and Earth are not the same.
C)The mass m is further from the Earth's center when it is on Mars.
D)The constant G is different on Mars.
E)The mass m will be different on Mars.

Accepted Answer

Weight is a measure of the force of gravity acting on an object, which is proportional to the mass of the object and the gravitational acceleration. The mass of the object does not change, but the gravitational acceleration on Mars is different than on Earth due to the difference in mass and radius of the two planets. Therefore, the weight of an object of mass m is different on Mars than it is on Earth.

Question 15

Two point masses m and M are separated by a distance d.If the distance between the masses is increased to 3d, how does the gravitational force between them change?
A)The force will be one-third as great.
B)The force will be one-ninth as great.
C)The force will be three times as great.
D)The force will be nine times as great.
E)It is impossible to determine without knowing the numerical values of m, M, and d.

Accepted Answer

According to the inverse square law, the gravitational force between two masses is inversely proportional to the square of the distance between them. So, if the distance between the masses is increased by a factor of 3, the force will be reduced by a factor of (1/3)^2 which is 1/9. Therefore, the correct option is B) The force will be one-ninth as great.

Question 16

Two satellites of different masses are in the same circular orbit around the earth.Which one of the following statements is true concerning the magnitude of the gravitational force that acts on each of them?
A)The magnitude of the gravitational force is zero newtons for both satellites.
B)The magnitude of the gravitational force is the same for both satellites, but not zero newtons.
C)The magnitude of the gravitational force is zero newtons for one, but not for the other.
D)The magnitude of the gravitational force depends on their masses.
E)The magnitude of the gravitational force varies from point to point in their orbits.

Accepted Answer

The answer of Two satellites of different masses are in...

Question 17

A book is resting on the surface of a table.Consider the following four forces that arise in this situation:
(1) the force of the earth pulling on the book (3) the force of the book pushing on the table
(2) the force of the table pushing on the book (4) the force of the book pulling on the earth
-Which two forces form an "action-reaction" pair that obeys Newton's third law?
A)1 and 2
B)1 and 3
C)1 and 4
D)2 and 4
E)3 and 4

Accepted Answer

The answer of A book is resting on the surface...

Question 18

A horse pulls a cart along a flat road.Consider the following four forces that arise in this situation.
(1) the force of the horse pulling on the cart (3) the force of the horse pushing on the road
(2) the force of the cart pulling on the horse (4) the force of the road pushing on the horse
-Which two forces form an "action-reaction" pair that obeys Newton's third law?
A)1 and 4
B)1 and 3
C)2 and 4
D)3 and 4
E)2 and 3

Accepted Answer

Newton's third law states that for every action, there is an equal and opposite reaction. Forces 3 and 4 are an action-reaction pair since the horse is pushing on the road and the road is pushing back on the horse with an equal and opposite force. Forces 1 and 2 do not form an action-reaction pair since they are both forces acting on the horse and the cart, respectively, and are not equal and opposite.

Question 19

Which one of the following statements concerning the two "gravitational constants" G, the universal gravitational constant, and g the magnitude of the acceleration due to gravity is true?
A)The values of g and G depend on location.
B)The values of g and G do not depend on location.
C)The value of G is the same everywhere in the universe, but the value of g is not.
D)The value of g is the same everywhere in the universe, but the value of G is not.
E)The values of g and G are equal on the surface of any planet, but in general, G varies with location in the universe.

Accepted Answer

The answer of Which one of the following statements concerning...

Question 20

A book is resting on the surface of a table.Consider the following four forces that arise in this situation: (1) the force of the earth pulling on the book (3) the force of the book pushing on the table (2) the force of the table pushing on the book (4) the force of the book pulling on the earth -The book has an acceleration of 0 m/s².Which pair of forces, excluding "action-reaction" pairs, must be equal in magnitude and opposite in direction? A)1 and 2 B)1 and 3 C)1 and 4 D)2 and 3 E)2 and 4

Accepted Answer

The answer of A book is resting on the surface...

Quiz 4: Forces and Newtons Laws of Motion

An astronaut orbits the earth in a space capsule whose height above the earth is equal to the earth's radius.How does the mass of the astronaut in the capsule compare to her mass on the earth?

A rock is thrown straight up from the earth's surface.Which one of the following statements concerning the net force acting on the rock at the top of its path is true?

Two point masses m and M are separated by a distance d.If the separation d remains fixed and the masses are increased to the values 3m and 3M respectively, how does the gravitational force between them change?

A 2.00-kg projectile is fired at an angle of 20.0°.What is the magnitude of the force exerted on the projectile when it is at the highest position in its trajectory? Neglect any effects of air resistance.

A 70.0-kg astronaut pushes to the left on a spacecraft with a force in "gravity-free" space.The spacecraft has a total mass of 1.0 × 10⁴ kg.During the push, the astronaut accelerates to the right with an acceleration of 0.36 m/s². -Determine the magnitude of the acceleration of the spacecraft.

An astronaut orbits the earth in a space capsule whose height above the earth is equal to the earth's radius.How does the weight of the astronaut in the capsule compare to her weight on the earth?

Consider the following forces. (1) frictional (2) gravitational (3) tension (4) strong nuclear (5) normal (6) electroweak Which of the forces listed are considered fundamental forces?

What is the weight of a 2.50-kg bag of sand on the surface of the earth?

Which one of the following statements best explains why the weight of an object of mass m is different on Mars than it is on the Earth?

Two point masses m and M are separated by a distance d.If the distance between the masses is increased to 3d, how does the gravitational force between them change?

Two satellites of different masses are in the same circular orbit around the earth.Which one of the following statements is true concerning the magnitude of the gravitational force that acts on each of them?

Which one of the following statements concerning the two "gravitational constants" G, the universal gravitational constant, and g the magnitude of the acceleration due to gravity is true?