Lesson 12.1.1

12.1.1 Gravitational fields and Newton's law of universal gravitation Quiz: Pearson Edexcel Physics, Unit 12

20 questions

Written by Revision Ninja · Last reviewed 11 October 2026

In partnership with Revision Ninja

Lesson 12.1.1, Gravitational fields and Newton's law of universal gravitation: 20 multiple choice questions for the Pearson Edexcel Physics (9PH0), Unit 12: Gravitational Fields, written with Revision Ninja.

Host it live on the board and students join with a game code on their own devices, or revise alone with Free Play. The answers are revealed in the game.

Host this setFree Play

The 20 questions

  1. What is a gravitational field?

    • A region in which light cannot travel.
    • A region in which a mass experiences a force due to other masses.
    • A magnetic region around a current-carrying wire.
    • A region in which charges always repel each other.

  2. How is gravitational field strength defined?

    • As the gravitational force per unit mass, g = F / m.
    • As the acceleration of a body in a vacuum only.
    • As the mass per unit volume of a planet.
    • As the gravitational potential energy per unit distance.

  3. What are the SI units of gravitational field strength?

    • kg m^-1
    • N kg^-1
    • J kg^-1 m
    • N m^-1

  4. What is the approximate value of the gravitational constant G?

    • 1.38 x 10^-23 J K^-1
    • 6.67 x 10^-11 N m^2 kg^-2
    • 9.81 N kg^-1
    • 6.02 x 10^23 mol^-1

  5. What is the direction of the gravitational force between two masses?

    • Perpendicular to the line joining their centres.
    • Attractive, but only when the masses are at rest.
    • Attractive, acting along the line joining their centres.
    • Repulsive, acting away from each other.

  6. Which equation gives the gravitational field strength due to a point mass M at distance r?

    • g = GM / r
    • g = G M^2 / r^2
    • g = GM / r^2
    • g = GM r^2

  7. Newton's law of universal gravitation is F = G m1 m2 / r^2. What happens to the force if the separation is doubled?

    • It is doubled.
    • It is quartered.
    • It is reduced to one eighth.
    • It is halved.

  8. Earth has mass 6.0 x 10^24 kg and radius 6.4 x 10^6 m. Using G = 6.67 x 10^-11 N m^2 kg^-2, what is g at its surface?

    • 2.5 N kg^-1
    • 0.98 N kg^-1
    • 98 N kg^-1
    • 9.8 N kg^-1

  9. Two masses of 1000 kg and 500 kg are 2.0 m apart. What is the gravitational force between them?

    • 3.3 x 10^-5 N
    • 8.3 x 10^-6 N
    • 1.7 x 10^-6 N
    • 8.3 x 10^-4 N

  10. A satellite is at a height above Earth equal to Earth's radius, so its distance from Earth's centre is 2R. What fraction of the surface value g0 is its field strength?

    • g0 / 2
    • g0
    • g0 / 8
    • g0 / 4

  11. The Moon has about 1/81 of Earth's mass and about 0.27 times its radius. Approximately what fraction of Earth's surface gravitational field strength is the Moon's surface field strength?

    • about 0.81
    • about 0.27
    • about 0.17
    • about 0.012

  12. A person of mass 70 kg stands on Earth where g = 9.8 N kg^-1. What is their weight?

    • 70 N
    • 7.1 N
    • 686 N
    • 9800 N

  13. At what distance from a point mass of 1.0 x 10^24 kg is the gravitational field strength 1.0 N kg^-1? Use G = 6.67 x 10^-11 N m^2 kg^-2.

    • 8.2 x 10^6 m
    • 6.7 x 10^13 m
    • 2.6 x 10^6 m
    • 8.2 x 10^3 m

  14. Why are gravitational forces always attractive, while electric forces can be repulsive?

    • Gravity acts only between masses, which are always positive, whereas charges can be positive or negative.
    • Masses are negative, so they always attract.
    • Electric forces are caused by gravity, which can act in either direction.
    • Gravity is weaker than electricity, so it can only pull.

  15. At the midpoint between two equal point masses, what is the net gravitational field?

    • Equal to the field of one mass, directed outwards.
    • Twice the field of one mass, directed towards the nearer mass.
    • Infinite, since the distance is zero.
    • Zero, since the two fields are equal and opposite.

  16. Why does g vary slightly over the surface of the Earth?

    • Gravity is zero at the equator, so g changes sharply there.
    • The Earth's mass changes from place to place by a large amount.
    • The Moon's gravity cancels out at some locations on the surface.
    • The Earth is not a perfect sphere, it rotates, and g depends on distance from the centre.

  17. Which is a correct use of the gravitational field strength formula g = F/m?

    • It gives the distance between two masses.
    • It gives the gravitational potential energy of a body.
    • It gives the field strength at a point from the force on a small test mass placed there.
    • It gives the mass of the field-producing body directly.

  18. A simple pendulum uses a bob of mass 0.50 kg. Its gravitational force is measured. Which quantity do you need to calculate g from F?

    • The amplitude of the swing only.
    • The mass of the bob, since g = F / m.
    • The length of the string only.
    • The period of the pendulum only.

  19. Which factor determines the gravitational field strength at a point due to a planet?

    • Its mass and the distance from its centre.
    • The temperature of its atmosphere.
    • Its orbital period about the Sun.
    • The colour of its surface.

  20. Two identical masses are placed at distances r and 3r from a point. What is the ratio of field strengths at the two points?

    • 3 : 1
    • 1 : 9
    • 9 : 1
    • 1 : 3

All Pearson Edexcel Physics quizzes