what is light? optics is the study of light light is a form of energy travels in straight lines is...

17

Upload: rafe-walsh

Post on 19-Jan-2016

216 views

Category:

Documents


1 download

TRANSCRIPT

Page 1: What Is Light? Optics is the study of light Light Is a form of energy Travels in straight lines Is transferred by radiation Is an electromagnetic wave
Page 2: What Is Light? Optics is the study of light Light Is a form of energy Travels in straight lines Is transferred by radiation Is an electromagnetic wave

What Is Light?

Optics is the study of light

Light • Is a form of energy• Travels in straight lines• Is transferred by radiation• Is an electromagnetic wave

Page 3: What Is Light? Optics is the study of light Light Is a form of energy Travels in straight lines Is transferred by radiation Is an electromagnetic wave

The Electromagnetic Spectrum

Page 4: What Is Light? Optics is the study of light Light Is a form of energy Travels in straight lines Is transferred by radiation Is an electromagnetic wave

The Electromagnetic Spectrum

Electromagnetic Wave: A wave that has both electric and magnetic parts, is radiated and travels at the speed of light

Electromagnetic Spectrum: The classification of electromagnetic waves by energy

Page 5: What Is Light? Optics is the study of light Light Is a form of energy Travels in straight lines Is transferred by radiation Is an electromagnetic wave

• Electromagnetic waves that the human eye can detect

• White light is composed of a spectrum of colours (ROYGBIV)

Page 6: What Is Light? Optics is the study of light Light Is a form of energy Travels in straight lines Is transferred by radiation Is an electromagnetic wave

Interactions of Light with Matter

Types of Materials:• Transparent: light passes through

– e.g. water, glass

• Translucent: light is scattered– e.g. frosted glass, stained glass

• Opaque: no transmission of light – e.g. stone, wood

Page 7: What Is Light? Optics is the study of light Light Is a form of energy Travels in straight lines Is transferred by radiation Is an electromagnetic wave

Light Can Be:Transmitted (passes through) Reflected (change direction)Absorbed (stopped from passing through)

Page 8: What Is Light? Optics is the study of light Light Is a form of energy Travels in straight lines Is transferred by radiation Is an electromagnetic wave

Properties of Light

1. Light always travels in straight lines

2. Light is invisible until reflected by translucent or opaque objects

3. Light can be transmitted, reflected or absorbed by different types of materials

Page 9: What Is Light? Optics is the study of light Light Is a form of energy Travels in straight lines Is transferred by radiation Is an electromagnetic wave

How is Light Produced

Luminous: Produces its own light (e.g. the sun, stars, a light bulb, a fire)

Non-Luminous: Does not produce its own light. Only visible when illuminated by a luminous source (e.g. the moon, a tree, a book, humans)

Most objects are non-luminous.However, there are many luminous

sources…

Page 10: What Is Light? Optics is the study of light Light Is a form of energy Travels in straight lines Is transferred by radiation Is an electromagnetic wave

Luminous Sources

INCANDESCENCE: • The production of light as a

result of high temperature• Examples:

Page 15: What Is Light? Optics is the study of light Light Is a form of energy Travels in straight lines Is transferred by radiation Is an electromagnetic wave

Luminous SourcesBIOLUMINESCENCE: • The production of light in living

organisms as the result of a chemical reaction with little or no heat produced

• Examples: