What g means: The gravitational field strength tells you how strong gravity pulls on each kilogram of mass. On Earth, g = 10 N/kg means every kilogram experiences a gravitational force of 10 Newtons.
g values on different bodies:
| Location | g value (N/kg) | Effect |
|---|---|---|
| Earth (surface) | 10 (use this!) | Standard — what we're used to |
| Moon | 1.6 | 6× less GPE for same height; astronauts could jump 6× higher |
| Mars | 3.7 | About 1/3 of Earth's gravity |
| Jupiter | 25 | 2.5× Earth's gravity — you'd feel very heavy! |
💡 Exam tip: Always use g = 10 N/kg unless the question tells you otherwise. Some exams use g = 9.8 N/kg for more precision, but 10 is standard for GCSE.
This key facts covers Understanding Gravitational Field Strength (g) within Gravitational Potential Energy for GCSE Physics. Revise Gravitational Potential Energy in Energy for GCSE Physics with 15 exam-style questions and 6 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 2 of 16 in this topic. Use this key facts to connect the idea to the wider topic before moving on to questions and flashcards.
Practice questions for Gravitational Potential Energy
What is the value of gravitational field strength (g) on Earth?
Explain how gravitational potential energy is related to an object's mass and height. Refer to the equation Ep = mgh in your answer.