P1 - topic 2 - Electromagnetic Waves Flashcards
what is the order of the electromagnetic spectrum?
radio waves micro waves infrared visible light ultra violet X-rays gamma rays
the EM waves are shown with their what?
wavelength
which EM wave has the smallest wavelength?
gamma rays
which EM wave have he smallest frequency?
radio waves
all EM waves are transverse/longitudinal?
transverse
all the different types of EM waves travel at the same speed or at different speeds in a vacuum?
the same
what speed do waves travel at in a vacuum?
3x20(8) m/s
give an example of a vacuum
space
EM waves like X-Ray’s and gamma rays and high frequencies but short what?
wavelength
who discovered infrared and when did they discover it?
Herschel in 1800
up until the discovery of infrared radiation, what was the only EM wave that scientists knew existed?
visible light
What did Herschel use to discover infrared?
a prism and sunlight
when light goes through a prism, what does it create?
a spectrum of colours
Herschel used a prism and sunlight to create a ……. on a …….
spectrum
screen
What did Herschel want to know about each of the colours in the spectrum?
the amount of heat in each of them
What did Herschel use to measure the heat in each of the colours in the spectrum?
a thermometer
what did Herschel notice about the temperature of the colours?
they increased from violet to red
When Herschel discovered the temperature increase from violet to red, what did he do next?
measure the temperature just last the red part of the spectrum where there’s no visible light
When Herschel measured the temperature just past the red part of the spectrum what did he find?
that there had the highest temperature of all
is infrared an visible or invisible type of radiation?
invisible
Who discovered ultraviolet radiation at when did they?
Ritter in 1801
What was Ritter trying to discover?
if there was anything of the other side of the spectrum beyond violet
What did Ritter know about silver chloride?
it turned from white to black when exposed to sunlight
What did Ritter measure?
How quickly silver chloride coated strips changed when exposed to different colours of light (the spectrum)
How did Ritter measure how quickly the silver chloride coated strips changed colour?
in a dark room, he created a spectrum using a light source and a prism and exposed the strips of paper to each colour. He timed how long it took the strips to turn black
A what end of the spectrum changed the stops the quickest when exposed to light?
blue
When Ritter discovered that the blue end of the spectrum changed the strips the quickest, what did he do?
He pleaded a trip in the area just past the violet part of the spectrum
What did Ritter discover when he place a strip just past the violet part of the spectrum?
he saw the quickest change of all
Is ultraviolet radiation an visible of invisible form of light that exists on the other side of the spectrum?
invisible light
how many EM waves are there?
7
What is the order of the colours in a spectrum?
red orange yellow green blue indigo violet
