Free Fall and Gravity
Free fall is motion under gravity alone, where all objects accelerate downward at about 9.8 metres per second squared near Earth.
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Free fall is motion under gravity alone, where all objects accelerate downward at about 9.8 metres per second squared near Earth.
- Air resistance is ignored in ideal free fall
- Heavy and light objects fall at the same rate in a vacuum
- Speed increases by about 9.8 m/s each second
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is Free Fall and Gravity?
Within Physics, which covers forces, energy, waves, electricity, magnetism, light and space explained through motion and experiments, this topic explains Free Fall and Gravity. Physics topics explain how things move, push, heat up and carry energy, so each one here pairs a definition with a live model you can change.
Check that you can explain Free Fall and Gravity in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding Free Fall and Gravity explains how the physical world behaves, from sport and transport to electricity and medicine.
Free Fall and Gravity in detail
Free fall is motion under the influence of gravity alone. Near Earth's surface all objects accelerate downward at about 9.8 m/s² (often rounded to 10 m/s²), regardless of mass, if air resistance is negligible. A hammer and a feather fall together in a vacuum.
The gravitational field strength g is also the weight per kilogram, 9.8 N/kg. Using equations of motion with a = g gives fall times and speeds. In air, resistance reduces the acceleration, and falling objects may reach a terminal velocity. Other planets and the Moon have different values of g.
How the interactive helps you understand Free Fall and Gravity
Watch the projectile path in the interactive. Use any sliders or buttons it offers to change the values and see how the projectile path responds.
Before you change anything, predict the result. Then change one value at a time and check whether your prediction was right. This is a quick way to build a correct mental model of Free Fall and Gravity.
Real-life uses and examples
- Answer “explain” questions by linking Free Fall and Gravity to a clear cause and effect.
- Predict what a ball, car or circuit will do with Free Fall and Gravity before you do the calculation.
- Explain everyday devices, such as brakes, lifts or chargers, using Free Fall and Gravity.
Common mistakes to avoid
- Forgetting that some quantities, such as force or velocity, also have a direction.
- Mixing up Free Fall and Gravity with a related quantity that has different units.
- Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.
Frequently asked questions about Free Fall and Gravity
What is Free Fall and Gravity?
Free fall is motion under gravity alone, where all objects accelerate downward at about 9.8 metres per second squared near Earth.
What are the most important points about Free Fall and Gravity?
The main points are: Air resistance is ignored in ideal free fall; Heavy and light objects fall at the same rate in a vacuum; Speed increases by about 9.8 m/s each second.
Why is Free Fall and Gravity useful?
Understanding Free Fall and Gravity explains how the physical world behaves, from sport and transport to electricity and medicine.
How can I practise Free Fall and Gravity?
Open the interactive at the top of this page and change the controls one at a time. Predict the result before each change, then take the three-question quiz. A score of two or more marks the topic as complete on this device.
Which topics are related to Free Fall and Gravity?
Related topics in Physics include Newton's Second Law, Friction, Moments and Levers.