A LevelPhysicsAQAExam QuestionsFields & Their ConsequencesOrbits of Planets & Satellites

Orbits of Planets & Satellites (AQA A Level Physics): Exam Questions

Exam code: 7408

3 hours31 questions

Select a download format for Orbits of Planets & Satellites

Scroll for more

Select an answer set to view for
Orbits of Planets & Satellites

Easy
Medium
Hard
1
1 mark

The gravitational force, FG , 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

2
1 mark

The Hubble telescope orbits the Earth once every 95 minutes.

What is the angular speed of the Hubble telescope's orbit?

  • 1.8×10−4 rad s−1

  • 1.1×10−3 rad s−1

  • 1.1×10−2 rad s−1

  • 6.6×10−2 rad s−1

Choose your answer

3
1 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

4
1 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

5
1 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

1
1 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?

  • 12mv2+GMmr

  • −GMr+12mv2

  • −GMmr

  • −GMmr+12mv2

Choose your answer

2
1 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 181 and the ratio of the radius of planet Y to the radius of planet X is 19. 

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

  • 1.1 km s–1

  • 3.3 km s–1

  • 5.0 km s–1

  • 30 km s–1

Choose your answer

3
1 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

4
1 mark

A satellite in a geostationary orbit has a linear speed of 3.1 km s−1.

What is the height of the satellite above the Earth's surface?

  • 29 600 km

  • 36 300 km

  • 42 600 km

  • 49 000 km

Choose your answer

5
1 mark

Two planets each of mass M and 6M have radii R1 and R2, respectively. The escape velocity at the surface of the planet of mass M is v, and the escape velocity at the surface of the planet of mass 6M planet is 4v.

What is the ratio R2R1?

  • 14

  • 38

  • 34

  • 32

Choose your answer

1
1 mark

A planet with the same mass and radius as the Earth rotates so rapidly that loose material at its equator only just remains in contact with the surface.

What is the period of rotation of the planet?

  • 1.4 hours

  • 6.3 hours

  • 10.2 hours

  • 18.1 hours

Choose your answer

2
1 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 = 3GMm4RE

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

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

  • RE

  • 2RE

  • 3RE

  • 4RE

Choose your answer

3
1 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 12mv2 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

4
1 mark

Satellites A and B have the same mass and move in circular orbits about the same planet at radii R and 2R, respectively. 

Which one of the following statements is correct?

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

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

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

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

Choose your answer

5
1 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 L1 and the other has a mass L2. Their orbiting planets, P1  and P2 have a mass of m1 and m2, and are observed to have identical orbits in shape and magnitude. 

If P1 completes an orbit in a quarter of the time taken by P2, which statement below can be reasonably deduced?

  • L1=L2 and m1=19m2

  • L1=16L2 and m1=m2

  • L1=14L2

  • L1=16L2 only

Choose your answer