1. Waves, Sound, and EM Waves

2. Sound Example of compressional wave Can travel through any type of matter Speed of sound depends on the substance the medium is made of and whether it is solid, liquid, or gas In solids, particles are closer together so particles can transmit energy more quickly Travel fastest in solids and slowest in gas

3. Sound Speed of sound in air = 347 m/s As the temperature of a substance increases, its molecules move faster so sound waves move faster

4. Reflection Reflection = Bouncing back of waves Angle of Incidence equals Angle of Reflection

5. Refraction – bending of waves

6. Diffraction – spreading of a wave

7. Electromagnetic Spectrum

8. Made of vibrating electric charges and can travel through space where matter is not present Energy transferred by vibrating electric and magnetic fields Speed of light 300000000 m/s Fastest in gases and slowest in solids

9. Radio Waves –AM radio waves, FM radio waves, Television Microwaves –Used in communication and heating foods Infrared Waves –Thermal energy –Hotter objects give off more IR waves than colder objects

10. Visible Light Detected with eye Colors –ROY G BIV –Red-Orange-Yellow Green Blue-Indigo-Violet Shortest wavelength – Blue Longest wavelength – Red

11. Gamma Rays Ultraviolet Waves –Useful in killing bacteria in objects X-rays –Can take images of organs, tissue, and teeth Gamma Rays –Used in radiation therapy