L5: electromagnetic spectrum Flashcards
(22 cards)
What types of radiation does the sun give?
Infrared (below red), light and ultraviolet
Which type of wave is light?
Transverse
What is light?
It is an electromagnetic wave and particle
What is the relation between freq and wavelength?
Long wavelength, small freq
What waves are on the electromagnetic spectrum (longer wavelengths to shorter)?
Radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, gamma
Where is visible light on the electromagnetic spectrum?
In the middle, it is a small part of the spectrum
Can you name three properties of EM waves?
Transverse waves, they travel at the speed of light (3x100000000 m/s), can travel through a vacuum
What is the unit of freq?
Hz
What does UV stand for?
Ultraviolet
What is the range of visible light?
From 400nm(violet) to 700nm (red)
What EM radiation has shorter wavelengths than violet?
Ultraviolet
What EM radiation has longer wavelengths than red?
Infrared
What is infrared radiation?
A type of heat
As the temp of the object increases, what happens to the intensity of the infrared radiation given off by the object?
The amount of infrared radiation given off increases. As it gets hotter, visible light is also emitted (e.g. red hot object)
Name three uses of infrared radiation?
In night-vision cameras, heaters and TV remote controls
What effect does infrared radiation have on us?
It heats us up
Can you name a use of radio waves?
Used to transmit radio and TV programmes (TV uses higher
frequencies)
Can you name a property of radio waves?
Can bend round hills and also reflect off upper atmosphere and so
able to travel long distances
What are microwaves the correct freq for?
To cause water molecules to vibrate, so they are used to heat food
Other than heating food, what are microwaves used for?
Communication (e.g. mobile phones)
What colours is visible light made of?
The rainbow (7 colours)
