# A tennis ball is dropped from rest and falls vertically downwards towards the ground. Explain why the ball accelerates as it falls, and state what happens to the acceleration as the ball gains speed.

> Edexcel GCSE Physics (1PH0) — 2.2 Forces and motion · Explain · 4 marks

> A tennis ball is released from rest at the top of a tall building and falls towards the ground.

## Mark scheme (4 marks)

1. Weight (gravitational force) acts downwards on the ball
2. Air resistance acts upwards on the ball (opposing motion)
3. Weight is greater than air resistance, so there is a resultant force downwards causing acceleration
4. As speed increases, air resistance increases, so the resultant force decreases and the acceleration decreases

## Key terms

- [acceleration](https://www.gradenine.co.uk/glossary/acceleration)

## Related

- [Revision notes for Edexcel GCSE Physics (1PH0)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/a-tennis-ball-is-dropped-from-12ec1e37) · Published by Druglandscape Ltd.