Across
- 3. the unit of pressure
- 5. power from falling water
- 9. sound cannot travel through it
- 11. the pressure of the air
- 12. the unit of resistance
- 14. the height of a wave
- 16. two connected bulbs side-by-side
- 19. it can be positive or negative
- 22. force / area
- 23. two bulbs connected one after the other
Down
- 1. it sank in 1912
- 2. from a crest to the next crest
- 4. a change in velocity
- 5. a safe gas for airships
- 6. the sun is mostly made of this
- 7. the extra length of a spring
- 8. a reflected sound
- 10. heat from inside the earth
- 13. a collection of electrical cells
- 15. the force that makes things float
- 17. it`s used to measure the current
- 18. it`s measured in joules
- 20. mass / volume
- 21. it stretches when a force is applied