1. CHAPTER 20 THE ENERGY OF WAVES

2. Waves - _________________________________________________________ **As the wave travels away from its source, energy moves through a ___________ but the ________________ does not move with the energy. The particles of the material move __________________ to the direction of the wave. The wave uses _______________ to do work on everything in its path. Energy transfer: 1. Through a medium. A medium is _____________________________ _________________________________________________________ Waves that require a medium are know as ________________________ and include:1. ___________________ 2. __________________________________ 3. __________________________________ 2. Waves that do not require a medium are know as ___________________ _____________ and include: 1. __________________________ 2. __________________________ 3. __________________________ 4. __________________________ These waves do not require a medium but can travel through substances such as ___________, _______________, and ______________. any disturbance that transmits energy through matter or space material perpendicular energy a substance through which a wave can travel, which can be solid, liquid, or gas mechanical waves Sound waves Water waves (ocean) Seismic waves (earthquakes) electromagnetic waves visible light TV and radio signals X-rays microwaves air water glass

3. Types of Waves 1. Transverse Waves - ___________________________________________ _____________________________________________________________ Example: a wave moving on a ______________All electromagnetic waves are classified as ____________________. waves in which the particles vibrate with an up and down motion, perpendicular to the direction the wave is traveling. rope crest trough transverse waves 2. Longitudinal Waves - _________________________________________ ____________________________________________________________ Example: a slinky or spring the particles of the medium vibrate back and forth along the path the wave travels wavelength amplitude Sound waves are examples of ______________________ waves. longitudinal

4. 3. Combinations of Waves - ________________________________________ ______________________________________________________________ a longitudinal and transverse wave can combine to form a surface wave at or near the boundary of 2 media. Example: ____________________________Ocean waves Properties of Waves: 1. Amplitude - _____________________________ _________________________________________ The larger the amplitude, the ____________ the wave and the more ____________ it carries. the maximum distance the wave vibrates from its rest position taller energy 2. Wavelength - __________________________________________________ _______________________________________________________________ the distance between 2 adjacent crests or compressions in a series of waves, or from a point on one wave to a corresponding point on the next wave. 3. Frequency - ___________________________________________________ _______________________________________________________________ The higher the frequency, the more ___________ pass by per _____________, and the higher the ______________. the number of waves produced in a given amount of time. Do this by counting the number of crests or troughs (or compressions or rarefractions) that pass by a certain point in one second. The unit is hertz where 1 Hz = 1 /second. wavessecond energy

5. 4. Wave speed - _________________________________________________ When v = _________________, λ = ____________________, and f = _____________________, you can use the following equation: v = ____ x ______ What is the frequency of a wave if it has a speed of 12 cm/s ad a wavelength of 3 cm?v = λ x f the speed at which a wave travels (distance / time) 12 cm/s = 3 cm x f______ _____ 3 cm 4/s = f 4 Hz = f A wave has a frequency of 5 Hz and a wave speed of 18 m/s. What is its wavelength?v = λ x f 18 m/s = λ x 5 Hz_____ ____ 5 Hz 3.6 m = λ wave speedwavelength frequency λ f

6. Wave Interactions 1. Reflection - __________________________________________________ Examples: Reflected light makes the ____________ shine. Reflected sound is called an ____________. when a wave bounces back after striking a barrier moon echo 2. Refraction - ___________________________________ _______________________________________________ the bending of a wave as it passes at an angle from one medium to another 3. Diffraction - ____________________________________________________ The amount of diffraction depends on the _________________ and _________ of the barrier or opening the wave encounters. _____________ waves are diffracted more than _____________ waves because they have a ____________ wavelength. The bending of waves around a barrier or through an opening wavelengthsize Sound lightlarger

7. 4. Interference - __________________________________________________ A. Constructive Interference - ________________________________ ________________________________________________________ B. Destructive Interference - _________________________________ ________________________________________________________ the result of 2 or more waves overlapping This occurs when the crests of one wave overlap the crests of another wave or waves This occurs when the crest of one wave and the troughs of another wave overlap.

8. C. Standing waves - _______________________________________ ________________________________________________________ These are waves that form a stationary pattern in which portions of the wave are at the rest position due to total destructive interference and other portions have a large amplitude due to constructive interference. D. Resonance - _______________ ____________________________ This happens because the second object absorbed ______________ from the original vibrating object. When an object vibrating at a frequency producing a standing wave causes another object to vibrate energy

9. CHAPTER 20 THE ENERGY OF WAVES

10. Waves - _________________________________________________________ **As the wave travels away from its source, energy moves through a ___________ but the ________________ does not move with the energy. The particles of the material move __________________ to the direction of the wave. The wave uses _______________ to do work on everything in its path. Energy transfer: 1. Through a medium. A medium is _____________________________ _________________________________________________________ Waves that require a medium are know as ________________________ and include:1. ___________________ 2. __________________________________ 3. __________________________________ 2. Waves that do not require a medium are know as ___________________ _____________ and include: 1. __________________________ 2. __________________________ 3. __________________________ 4. __________________________ These waves do not require a medium but can travel through substances such as ___________, _______________, and ______________.

11. Types of Waves 1. Transverse Waves - ___________________________________________ _____________________________________________________________ Example: a wave moving on a ______________All electromagnetic waves are classified as ____________________. 2. Longitudinal Waves - _________________________________________ ____________________________________________________________ Example: a slinky or spring Sound waves are examples of ______________________ waves.

12. 3. Combinations of Waves - ________________________________________ ______________________________________________________________ Example: ____________________________ Properties of Waves: 1. Amplitude - _____________________________ _________________________________________ The larger the amplitude, the ____________ the wave and the more ____________ it carries. 2. Wavelength - __________________________________________________ _______________________________________________________________ 3. Frequency - ___________________________________________________ _______________________________________________________________ The higher the frequency, the more ___________ pass by per _____________, and the higher the ______________.

13. 4. Wave speed - _________________________________________________ When v = _________________, λ = ____________________, and f = _____________________, you can use the following equation: v = ____ x ______ What is the frequency of a wave if it has a speed of 12 cm/s ad a wavelength of 3 cm?v = λ x f A wave has a frequency of 5 Hz and a wave speed of 18 m/s. What is its wavelength?v = λ x f

14. Wave Interactions 1. Reflection - __________________________________________________ Examples: Reflected light makes the ____________ shine. Reflected sound is called an ____________. 2. Refraction - ___________________________________ _______________________________________________ 3. Diffraction - ____________________________________________________ The amount of diffraction depends on the _________________ and _________ of the barrier or opening the wave encounters. _____________ waves are diffracted more than _____________ waves because they have a ____________ wavelength.

15. 4. Interference - __________________________________________________ A. Constructive Interference - ________________________________ ________________________________________________________ B. Destructive Interference - _________________________________ ________________________________________________________.

16. C. Standing waves - _______________________________________ ________________________________________________________ D. Resonance - _______________ ____________________________ This happens because the second object absorbed ______________ from the original vibrating object.