1. Waves and Energy Transfer Surf’s Up Braaaaaaaaaaaaah

2. Waves and Energy Transfer A wave is an oscillation accompanied by energy that travels through space or mass. Mechanical waves require material to travel through, like sound waves, water waves, springs or ropes. Electromagnetic waves travel through space, therefore do not require a medium. They have a fixed speed of 299,792,458 m/s. We call this c = speed of light.

3. Waves and Energy Transfer Two types of mechanical waves Transverse Wave = particles of the medium vibrate perpendicular to the direction of motion (ex. guitar strings) Longitudinal (Compression) Wave = particles of the medium vibrate along with the direction of the motion (ex. water waves)

4. Waves and Energy Transfer For Transverse Waves: The peaks are called crests, and the dips are called troughs. For Longitudinal Waves: The dense parts are called compressions and the spaced out parts are called rarefactions.

6. Waves and Energy Transfer The distance between two crests, two troughs, two compressions etc. is the wavelength How often a vibration occurs per second is the frequency The units for frequency is hertz (Hz). It is the same as 1/seconds

7. Waves and Energy Transfer

8. Waves

9. Waves and Energy Transfer The amplitude of a wave is the maximum displacement the wave has from its equilibrium point. For compressional waves its how dense the compressions are

10. Waves and Energy Transfer The energy a wave has varies as the square of the amplitude If you double the amplitude of a wave, you quadruple the energy. 2 x Amplitude -> 2² x Energy The wavelength and frequency can also affect the energy a wave has.

11. Waves and Energy Transfer Assignments for period 8 Worksheet handout, due ASAP Book problems pg 293 1-4, due Wednesday 1/27 For number 3 and 4 remember the speed of light.