Wave Interaction

Reflection, Refraction, Diffraction &
Absorption
•When waves encounter different
media, they are either
•reflected
•refracted
•diffracted
•absorbed.

Reflection, Refraction, Diffraction &
Absorption

This means when they go from 1
medium to another medium

Transmission

When waves are transmitted, they
continues through the material.

Reflection

•Reflection: wave bounces off & goes in a different direction

Reflection

•Reflection: wave bounces off & goes in a different direction

Refraction
•Refraction: bending of light as it moves from 1 medium to another

Refraction

A refracted wave is a wave that has changed direction (bent) by
moving from one material to another material of different
density BECAUSE THE LIGHT CHANGES SPEED in the NEW
MEDIUM

Diffraction

Diffraction refers to various phenomena that occur when a wave
encounters an obstacle or opening. It is defined as the bending of
waves around the corners of an obstacle or through an opening

Diffraction

Absorption

In ABSORPTION, the ENERGY of the WAVE is transferred to the material
it encounters

Colors are caused by reflection

Objects appear different colors because they absorb some colors (wavelengths)

and reflected or transmit other colors. The colors we see are the wavelengths

that are reflected or transmitted. ...

White objects appear white because they reflect all colors.

Black objects absorb all colors so no light is reflected.

Absorption

•Absorption: the energy is absorbed by the material

Scattered

Scattering is unique in that the wave energy is generally
deflected in multiple directions that are difficult to predict
or calculate.

Wave Interference

•Constructive Interference: 2 waves of similar size colliding & forming a
wave w/an amplitude greater than either wave

Wave interference

•Destructive Interference: 2 waves of similar size combine to form a
wave with a smaller amplitude than either wave.

Standing Waves

•A wave that appears to stand still because 2 waves are interfering
with each other.

Resonance

•Most object have a natural frequency of vibration
•Standing wave are produced when the object vibrates at 1 of the
natural frequencies
•If a nearby object vibrates with the same frequency, it causes a
RESONANCE (The nearby object begins to vibrate also)

Diffraction

•Waves bending around objects

Diffraction model

Key Topics

1) Rank the Speed of a mechanical wave in solids, liquids

& gases

2) Rank the speed of EM waves in solids, liquids & gases

3) Compare and contrast transparent, translucent &

opaque

4) Compare and contrast Reflection, refraction,

absorption & diffraction

5) Compare and contrast Constructive interference &

destructive interference

6) Describe a Standing Wave

7) Explain Resonance