Wave Interactions and Behaviors

Wave Behaviors Transmission: Occurs when waves pass

through a given point or medium. example: Sound waves transmitted thru solids, liquids and

gases. Radio waves are transmitted through one electron through another.

Light waves are transmitted – 3 ways light and matter can pass through material.

A. Transparent material: Only a small amount of light is reflected or absorbed (may be clear or colored material such as filters, windows).

B. Opaque material: allows no light waves to be transmitted through them.

C. Translucent materials: Transmit some light, but cause it to be scattered so no clear image is seen.

Wave BehaviorsAbsorption--occurs when the energy is not transferred through or reflected by the given mediumDisappearance of an electromagnetic wave into a medium.

Opposite of reflection

We see colors because of the selective absorption of visible light.

Objects absorb certain wavelengths and we see what is leftover.

The colors we see depend on the wavelength absorbed.

Absorption

Orange

Yellow GreenBlue

Violet

RedRed

The apple absorbs all wavelengths except red.

The apple reflects mostly red. Therefore, it looks like red.

Essay question on test!!!

Absorption A material that absorbs all wavelengths of

visible light will appear black.

In contrast, a material that reflects all wavelengths will appear white.

Objects or substances that absorb any wavelength of EM radiation become warmer and convert the absorbed energy to infrared radiation. (GREENHOUSE EFFECT)

Wave BehaviorsA. Reflection– bouncing back of a wave as it

meets a boundary or surface (pg.

- Examples: Echoes, Looking in a mirror

Wave BehaviorsB. Refraction– bending of waves as they pass

from one medium to another (pg.

Wave BehaviorsC. Diffraction– bending of waves around an

edge (Pg.

Wave Interactions

D. Interferance –

combination of 2 or more waves

usually produces one wave

(bigger if in phase)

(smaller if out of phase)

Wave InteractionsConstructive interference – when

waves combine to create a bigger wave

sum of the amplitudes of the waves

Examples: Pg.

Wave Interactions2. Destructive interference – when waves combine to form a smaller or no wave

some may completely cancel out difference between the amplitudes of the waves- Example: Pg.

Wave Interactions E. Wave speed depends on

the mediumex. Sound moves fastest through

solids moves moderately fast

through liquids moves slowest through

air/gases (340 m/s)

- due to movement of molecules in the medium

Wave InteractionsF. Light travels at a constant speed

3x 108 m/s = 300,000,000 m/s (186,000 miles/sec.)