Waves and Properties of Waves Physics

Waves A disturbance that carries energy through matter or empty space while moving from 1 place to another. They propagate. What do waves carry? – They carry energy, not matter.

What transports a wave’s Energy? Substances that waves carry their energy through are Mediums or empty space. Ex: – Solids – Liquids – Gases

Wave Pulse A short length of a wave.

Mechanical Waves Mechanical Waves must always have a medium to travel through or to transfer energy. 2 Types- – 1) Transverse Waves – 2) Longitudinal Waves

Transverse Waves Transverse Waves: – Cause the medium to vibrate perpendicular to the direction the wave is moving. Parts: – 1) Crest- The top part of a wave. – 2) Trough- The lowest part of a wave. Ex: – A guitar string being plucked – Rock that is thrown into a pond

Wave Diagrams Transverse Waves- – rtsOfAWave/waveParts.htm rtsOfAWave/waveParts.htm Longitudinal Waves- – s/wavemotion.html s/wavemotion.html – /waves/u10l1c.html /waves/u10l1c.html – astr.gsu.edu/hbase/sound/tralon.html astr.gsu.edu/hbase/sound/tralon.html

Longitudinal Waves Cause the medium to vibrate parallel to the direction the wave is moving. Parts: – Compression- Parts of a wave where the particles are pushed or compressed together. – Rarefaction- Parts of a wave where the particles are spread apart. Ex: Sound

Wave Diagrams Transverse Waves- – rtsOfAWave/waveParts.htm rtsOfAWave/waveParts.htm Longitudinal Waves- – s/wavemotion.html s/wavemotion.html – /waves/u10l1c.html /waves/u10l1c.html – astr.gsu.edu/hbase/sound/tralon.html astr.gsu.edu/hbase/sound/tralon.html

Electromagnetic Waves Can travel through both mediums and empty space. Ex: – Light – Gamma Rays

Standing Waves Waves that are produced when they are confined/trapped between boundaries. Cause the waves to interfere with their own reflections. Examples: – Sound – Water

Surface Waves Type of waves that cause the medium to move in a circle. Ex: – Earthquakes – Ocean Waves

Absorption A decrease in amplitude of waves as they pass through a material and lose energy. – The waves will disappear. – The energy of the waves are being absorbed by the material. Ex: – Sunglasses absorb sunlight.

Absorption

Superposition Principle States that when 2 or more waves overlap, the wave that formed is the sum of the individual waves. rposition/superposition.html rposition/superposition.html

Differences between Sound and Light Waves. 1) Sound Waves must have a Medium to travel through and Light Waves can travel through matter and empty space. 2) Sound Waves can travel through all substances. 3) Light travels Faster than Sound.

Quiz- 5/2/12, 5/3/12 1) What is the wavelength of a wave that has a period of 2.95 minutes and a wave speed of 8.90 m/s? 2) Which wave behavior (Reflection, Refraction, Diffraction, Absorption) is occurring when a quarter looks closer to the surface of the water when a person is looking at it in a wishing well. 3) Draw a wave and label the following parts- Wavelength, Amplitude, Crest, Trough 4) Determine the frequency of a wave that has a period of 32.9 seconds.

Quiz- 5/2/12, 5/3/12 5) What happens to the wavelength of a wave if the energy of the wave decreases? 6) What happens to the frequency of a wave if the wavelength of the wave gets shorter (decreases)? 7) Determine the wave speed of a wave that has a period of 1.35 minutes and a wavelength of 0.56 m. 8) 2 waves come together and form a single, larger wave for a moment is an example of _____________________. 9) How are electromagnetic and mechanical waves different? 10) Determine the period of a wave that has a wavelength of 0.05 and a wave speed of 4.78 m/s.