AQA A Level Physics

Topic Questions

A LevelPhysicsAQATopic Questions7. Fields & Their Consequences7.3 Orbits of Planets & Satellites

7.3 Orbits of Planets & Satellites

DownloadView
Easy
Medium
Hard
Easy
Medium
Hard
11 mark

The gravitational force, F subscript G , keeps the Earth in a (near) circular orbit around the Sun, as shown in the diagram below.

7-3-mcq-q1-easy-aqa-a-level-physics

What type of force is responsible for keeping the Earth in a circular orbit? 

  • A contact force

  • A centrifugal force

  • An electrostatic force

  • A centripetal force

Choose your answer

Did this page help you?

21 mark

The Hubble telescope orbits Earth at a blistering speed of about 7600 m s–1. 

The radius of its orbit is about 7000 km, as shown in the figure below:

7-3-mcq-q2-easy-aqa-a-level-physics

How long does it take the Hubble telescope to complete one full orbit of Earth?

  • 1.6 hours

  • 5800 hours

  • 96 hours

  • 24 hours

Choose your answer

Did this page help you?

31 mark

What is a correct expression for the total energy of an object in orbit?

  • Total energy = Kinetic energy

  • Total energy = Kinetic energy + Potential energy

  • Total energy = Potential energy 

  • Total energy = Potential energy + Thermal energy

Choose your answer

Did this page help you?

41 mark

Which sentence best describes the relationship between the time period T of an object in a circular orbit and the orbital radius r?

  • The time period T is equal to the orbital radius r 

  • The time period T is inversely proportional to the radius r of the orbit

  • The square of the time period T2 is proportional to the cube of the radius r3 

  • The time period T is double the orbital radius r

Choose your answer

Did this page help you?

51 mark

Which of the following statements about satellites in geostationary orbits is correct?

  • Satellites in geostationary orbits stay above the poles of Earth

  • Satellites in geostationary orbit appear to move across the sky

  • The orbital period of a satellite in geostationary orbit is 24 hours

  • Satellites in geostationary orbits move from east to west

Choose your answer

Did this page help you?

11 mark

How long would the length of one Earth-day be, if the planet were to rotate so rapidly that material at its equator only just remains on the surface?

  • 1.4 hours

  • 6.3 hours

  • 10.2 hours

  • 18.1 hours

Choose your answer

Did this page help you?

21 mark

A space probe is launched from the surface of the Earth’s equator into orbit. 

The total energy E given to the space probe of mass m is: 

            E = fraction numerator 3 G M m over denominator 4 R subscript E end fraction

where G is the gravitational constant and M and R subscript E are the mass and radius of Earth, respectively. 

What is the height of the space probe’s orbit above the Earth’s surface?

  • R subscript E

  • 2 R subscript E

  • 3 R subscript E

  • 4 R subscript E

Choose your answer

Did this page help you?

31 mark

Which of the following statements about objects in orbits is correct?

  • The total energy of an object in orbit is positive

  • The total energy of a comet when it is closest to the sun is equal to begin mathsize 16px style 1 half end stylemv2 where m is its mass and v is its orbital velocity 

  • An object does not need to travel at the escape velocity of a planet in order to be put into orbit

  • The energy required to launch an orbiting satellite out of Earth’s gravitational influence is more than the energy required to launch a stationary object (at the same height) out of Earth’s influence

Choose your answer

Did this page help you?

41 mark

Two satellites, A and B, of equal mass, are in orbit around Saturn at radii R and 2R respectively. 

Which one of the following statements is correct?

  • A has more kinetic energy and less potential energy than B

  • A has more kinetic energy and more potential energy than B

  • A has less kinetic energy and more potential energy than B

  • A has less kinetic energy and less potential energy than B

Choose your answer

Did this page help you?

51 mark

Two planetary systems are very far apart in space, but the properties of the orbiting planets are interesting and can be compared. 

One of the suns has a mass begin mathsize 16px style L subscript 1 end style and the other has a mass L subscript 2. Their orbiting planets, P subscript 1  and P subscript 2 have a mass of m subscript 1 and m subscript 2, and are observed to have identical orbits in shape and magnitude. 

If P subscript 1 completes an orbit in a quarter of the time taken by P subscript 2, which statement below can be reasonably deduced?

  • L subscript 1 equals L subscript 2 and m subscript 1 equals 1 over 9 m subscript 2

  • L subscript 1 equals 16 L subscript 2 and m subscript 1 equals m subscript 2

  • L subscript 1 equals 1 fourth L subscript 2

  • L subscript 1 equals 16 L subscript 2 only

Choose your answer

Did this page help you?

11 mark

A comet of mass m is in an elliptical orbit around the Earth, as shown in the figure below:

7-3-mcq-q1-medium-aqa-a-level-physics

It is moving at a speed v when it is at a distance r from the Earth. The mass of the Earth is M. 

What is the total energy of the comet at P?

  • 1 half m v squared plus fraction numerator G M m over denominator r end fraction

  • negative fraction numerator G M over denominator r end fraction plus 1 half m v squared

  • negative fraction numerator G M m over denominator r end fraction

  • negative fraction numerator G M m over denominator r end fraction plus 1 half m v squared

Choose your answer

Did this page help you?

21 mark

Planet X and Planet Y exist in a galaxy far, far away. 

The escape velocity from the surface of planet X is about 10.0 km s–1. The ratio of the mass of planet Y to the mass of planet X is begin mathsize 16px style 1 over 81 end style and the ratio of the radius of planet Y to the radius of planet X is begin mathsize 16px style 1 over 9 end style. 

What is the best estimate for the escape velocity from the surface of the planet Y?

  • 3.3 km s–1

  • 1.1 km s–1

  • 30 km s–1

  • 5.0 km s–1

Choose your answer

Did this page help you?

31 mark

A satellite in a stable circular orbit around the Earth is moved to a higher stable circular orbit. 

Which of the following statements is incorrect?

  • The angular speed of the satellite decreases

  • The gravitational potential energy of the satellite increases

  • The linear orbital speed of the satellite increases

  • The gravitational force on the satellite decreases

Choose your answer

Did this page help you?

41 mark

A satellite of mass m is placed in a geostationary orbit. 

If the Earth’s angular velocity is 7.0 × 10–5 rad s–1, what is the circumference of the satellite’s orbit?

  • 4.0 × 109 m 

  • 2.9 × 1011 m

  • 1.8 × 106 m 

  • 2.7 × 108 m

Choose your answer

Did this page help you?

51 mark

Two spherical moons have masses M and 5M and radii r subscript 1 and r subscript 2 respectively. The escape velocity at the surface of planet with mass M is 0.5 × 104 m s–1 and the escape velocity at the surface of the other planet with mass 5M is 2 × 10­4 m s–1. 

What is the ratio r subscript 2 over r subscript 1 ?

  • 5 over 4

  • 5 over 16

  • 3 over 9

  • 3 over 81

Choose your answer

Did this page help you?