Visible light and colour

what is the acronym to remember the colours of visible light

R- red

O- orange

Y - yellow

G- green

B - blue

I - indigo

V - violet

violet has the ______ wavelength and ________ frequency

shortest wavelength and highest frequency

red has the _______ wavelength and ________ frequency

longest wavelength and lowest frequency

why isn't black on the spectrum

because it it just the absence of light

why isn't white on the spectrum

because it's a combination of all the colours/wavelengths of the spectrum

What are opaque objects?

Objects that do not transmit light. When visible light waves hit them, they absorb some wavelengths of light and reflect others (eg. yellow cheese reflects either yellow or a combination of red and green so that is why it appears yellow)

what are transparent objects

Objects that light can travel through, they transmit nearly all the light and only a small fraction is absorbed or reflected

what are translucent objects

Objects that allow some but not all light to pass through them, they are partially see through, the proportion of light they transmit determines how well we can see through them

how do primary colour filters work

they only allow the wavelength of one of the primary colours to be transmitted, which is the same colour of the colour filter, any other primary colours will be absorbed and so the filter will appear black

how do secondary colour filters work

they only allow wavelengths of the same colour as the filter to be transmitted and the wavelengths of the primary colours that can be added together to make that colour