Across
- 3. The phenomenon in which light above a certain frequency knocks electrons loose from atoms of certain metals.
- 5. English physicist who proposed the particle theory of light.
- 7. The phenomenon that occurs when light rays from a distant object are refracted by heated air so that the object appears to be nearby.
- 11. Electromagnetic waves that our eyes can perceive.
- 12. A system that emits sound waves underwater and analyzes the echoes reflected from submerged objects.
- 16. The phenomenon in which the colors of light depend on the viewing angle.
- 18. Bending of the path of a wave as a result of a change in wave speed.
- 20. The change in a wave's frequency caused by an object's motion.
- 21. The effect of frequency on the way the ear perceives sound.
- 23. Maximum distance that particles are displaced by a wave.
- 25. A spherical mirror that has the reflecting side on the outside of the spherical surface is a ________ mirror.
- 26. The additive primary colors of light are red, _______, and blue.
- 29. Reinforcement or cancellation that occurs when two or more waves meet.
- 31. The unit usually used to measure sound intensity level.
- 32. Spreading out of a wave after it passes through a narrow opening.
- 35. German physicist who demonstrated the existence of radio waves.
- 36. The bright fringes formed when light passes through a narrow slit.
- 39. Low-frequency electromagnetic waves widely used for communications.
- 40. Electromagnetic waves used for cooking
- 41. The scientist who discovered the special theory of relativity.
- 42. Because it has light of only a single frequency, a laser beam is said to be _______________.
- 43. The SI unit of frequency.
Down
- 1. Number of waves that pass a given point per unit of time.
- 2. Dutch physicist who proposed the wave theory of light.
- 4. Calculating distance from the time between the sending of a sound wave and the return of the echo.
- 6. The phenomenon that occurs when light passes through a glass plate with parallel, microscopic grooves on it.
- 8. The study of sound.
- 9. Light is said to consist of tiny bundles or "packets" of energy called _________.
- 10. The principle stating that the angle of incidence equals the angle of reflection.
- 13. An image that appears to be behind a mirror.
- 14. The apparent change in time for a rapidly moving object is called time ___________.
- 15. Magenta, cyan, and yellow.
- 17. The effect of intensity on the way the human ear perceives sound.
- 19. The idea that gravity is caused by the geometry of space.
- 22. Sound that has too low a frequency to be heard.
- 24. The property that describes a beam of light whose waves are all aligned in the same direction.
- 27. The main factor affecting the speed of sound in air is the air _____________.
- 28. Electromagnetic waves sometimes called "heat rays".
- 30. Scottish physicist who demonstrated that light consists of two transverse waves oscillating at right angles to each other.
- 33. The substance through which a wave transfers its energy.
- 34. A loud noise caused by a shock wave.
- 37. The theory that light has a dual nature, with characteristics of both particles and waves, is the _________ theory of light.
- 38. The most powerful and penetrating electromagnetic waves.