Across
- 3. Has many bumps and hollows
- 5. Air friction that slows down a plane, car etc.
- 9. Force pushing on something
- 11. Go faster
- 12. The force created when one surface moves against another
- 14. To move smoothly across a surface
- 16. Go slower
- 17. An aeroplane has two whats?
- 18. Like strength or power
Down
- 1. Put oil or other liquid between two surfaces
- 2. The force that moves a plane forwards
- 4. The moving blades of a helicopter
- 6. The outside part or top layer of something
- 7. The force pulling things down towards the Earth
- 8. Describes an object designed to reduce drag and air friction, eg. the nose of an aeroplane
- 10. To pull something upwards
- 13. Make something greater in size or amount
- 15. Make something less in size or amount