Light Flashcards
What are objects that produce their own light called?
Luminous sources
What are objects that we need light to see them called?
Non-Luminous sources
What are things we can see light through called?
Transparent
What are thing we can’t see light through called?
Opaque
What do rays of light do when they cross the boundary between two different transparent substances?
They slow down and change direction towards the normal line
What are the colours of the rainbow
Red
Orange
Yellow
Green
Blue
Indigo
Violet
How does light travel?
In a straight line
How are eclipses formed?
When the earth, moon and sun are all in line
What is the difference between solar eclipse and lunar eclipse?
Solar- the moon casts its shadow onto the earth
Lunar- the moon moves into the earths shadow
What is the law of reflection?
The angle of incidence is always the same as the angle of reflection
What does dispersion mean?
When white light is separated into colours
Give 4 examples of luminous objects
Sun
Lightbulb
TV
Phone
Give 3 examples of non-luminous objects
Moon
Windows
Mirror
Define translucent
Allows some light to pass through
What are the 4 properties of light?
Travels in straight lines
Can travel through a vacuum (requires no particles to travel)
Travels at 300 million m/s
Travels faster than sound
Name all the parts of the electro magnetic spectrum
Red- Radio
Meerkats- Microwave
In- Infrared
Vienna- Visible
Use- Ultraviolet
X-ray- X-ray
Gadgets- Gamma ray
Name 2 properties of Radio waves
They are used for tele communication
TV and radio
Detected with an ariel and reciver
Name 2 properties of microwaves
Used for cooking
Detected by an ariel
Phones and rada can receive microwaves
Name 2 properties of infrared waves
Heat or thermal energy detected by electronic devices or thermometers
Used in astronomy, night vision
Name 2 properties of visible waves
Photography
Laser surgery
optical communication
Danger- blindness
Name properties of ultraviolet waves
Sterilise medical equipment
Detects fake bank notes
Danger- sun burn, skin cancer, blindness
Name properties of X-rays
Shows bones in the body
Detected using film
Danger- cell destruction, cancer
Name properties of gamma rays
Radio therapy to kill cancer
Studying supernova
Detected by Geiger-muller tubes
Danger- cell destruction, cancer
