2. Pg. 31 10/10/13

4. Waves and the Electromagnetic Spectrum A wave is a disturbance that transfers energy from place to place. Most waves need something to travel through - such as waves that travel along the surface of water. The material through which a wave travels is called a medium.

5. How do waves transfer energy? Energy is required to make a wave. Mechanical waves: produced when a source of energy causes a medium to vibrate. A vibration is a repeated back-and forth or up-and-down motion. Waves transfer energy to the medium’s particles, passing the wave’s energy along.

6. Properties of Waves The high point of a wave is called the crest, and the low point is the trough. The distance the medium rises depends on the amplitude of the wave. Amplitude is the max. distance particles of a medium move away from their rest position as a wave passes through the medium.

7. Draw and label this in your notes: Parts of a Wave

8. Wavelength and Frequency Wavelength is the distance between one point on a wave and the corresponding point on an adjacent wave. Frequency is the number of waves produced in a given amount of time. It is measured in units called hertz (Hz). Speed is how far a wave travels in a given amount of time.

10. Electromagnetic Spectrum The entire range of EM waves is called the electromagnetic spectrum. Waves in the EM spectrum can transfer energy without a medium. The EM spectrum is arranged from long to short wavelengths and from low to high frequency.

12. Place the following EM wave in order from low to high frequency. Use pg 44 & 45 in the book to help you. Gamma rays X-rays Radio waves Infrared waves Visible light Microwaves Ultraviolet light

13. The correct order is: 1. Radio waves 2. Microwaves 3. Infrared rays 4. Visible light 5. Ultraviolet rays 6. X-rays 7. Gamma rays

14. Work with your shoulder partner to write questions. Finish summary for homework.