ANSWERS TO QUESTIONS Q1. THROUGH Q48.

A1. Propagation means spreading out.
A2. A wave is a disturbance which moves through a medium.
A3. A means of transferring energy from one place to another.
A4. Sound waves, light waves, radio waves, heat waves, water waves.
A5. Transverse waves.
A6. Radio waves, light waves, and heat waves.
A7. A sound wave.
A8. A source, medium, and detector (receiver).
A9. A sequence of events, such as the positive and negative alternation of electrical current.
A10. The space occupied by one cycle of a radio wave at any given instant.
A11. The law of reflection states: The angle of incidence is equal to the angle of reflection.
A12. When the incident wave is nearly parallel with the surface.
A13. When the incident wave is perpendicular to the surface. Also a dull (or black) surface reflects very little regardless of the angle.
A14. The density of the two mediums, and the velocity of the waves.
A15. The Doppler effect.
A16. Sonics.
A17. No. The average human ear cannot hear all sounds in the infrasonic and ultrasonic regions.
A18. An amplifier.
A19. A source, medium, and detector (receiver).
A20. Noise and tones.
A21. Pitch, intensity, and quality.
A22. 20 Hz to 20 kHz.
A23. The amount of energy transmitted from a source.
A24. Quality.
A25. Velocity increases as density decreases and temperature increases.
A26. Acoustics.
A27. Echo.
A28. Reverberation.

A29. Resonance.
A30. Noise.
A31. Mechanical, electrical, and chemical.
A32. A photon.
A33. Angstrom unit.
A34. Red, green and blue.
A35. Magenta, yellow and cyan.
A36. Reflected or absorbed.
A37. None, all colors would be absorbed.
A38. Translucent.
A39. 186,000 miles per second or 300,000,000 meters per second.
A40. Transmitted.
A41. Diffused.
A42. Light waves, heat waves, and radio waves.
A43. The visible spectrum can be seen.
A44. Electric field and magnetic field.
A45. An antenna.
A46. Electric field.
A47. Magnetic field.
A48. Radiation field.