Invisible Waves

6. The distance from any point on a wave to the same point on the next wave
7. Sound cannot pass through this
10. All waves transfer _______ not matter
11. Short wavelength sounds have a high ______
12. The bottom of a wave
14. The maximum displacement from the baseline or resting state
16. Heat transfer by currents in fluids
19. Used by ships to find fish and the ocean floor
20. Light and sound are forms of this
21. An area in a longitudinal wave where particles are pressed together
23. Sound travels ______ in solids than in gases
24. Energy can be ______ from one form to another
26. A wave where the particle oscillate in the same direction as direction of travel

1. The substance through which waves travel
2. Sound above human hearing (20,000 Hertz), often used to check unborn babies.
3. Created by aircraft and Mr Elith travelling faster than the speed of sound
4. bouncing sound off objects used by dolphins and bats to navigate and find food
5. A material that transfers heat easily
8. Heat transfer from particle to particle
9. A material that does not allow heat to be transferred
11. These convert light into electrical energy
13. Heat transfer through EM waves
15. A wave where the particle oscillate at right angles to direction of travel
17. Another name for heat
18. An area in a longitudinal wave where particles are spread far apart
21. The top of a wave
22. The number of waves or cycles per second
25. Sound is produced by something that is ______