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# Visible Light watch

1. The student looks at a red football and a white football both through a green filter.
State and explain what colour each football appears.

Would the red ball turn black because it is not made from green light so all of the reflected light would be absorbed by the filter?

And would the white ball turn green? I don’t know why though.

Any help is great thanks
2. Yeah I presume there's white light shining on both balls. white is a mixture of all visible wavelengths.

The red football reflects only red wavelengths and absorbs all other wavelengths
The while football reflects all wavelengths

The green filter absorbs all wavelengths except green - green wavelengths are transmitted

so the light reflected off the white football is a mixture of all wavelengths which then has all wavelengths except green absorbed in the filter & green is transmitted (making the ball look green)
but the light reflected off the red football only has red wavelengths, when the filter absorbs all wavelengths except green there is no light left
3. (Original post by Joinedup)
Yeah I presume there's white light shining on both balls. white is a mixture of all visible wavelengths.

The red football reflects only red wavelengths and absorbs all other wavelengths
The while football reflects all wavelengths

The green filter absorbs all wavelengths except green - green wavelengths are transmitted

so the light reflected off the white football is a mixture of all wavelengths which then has all wavelengths except green absorbed in the filter & green is transmitted (making the ball look green)
but the light reflected off the red football only has red wavelengths, when the filter absorbs all wavelengths except green there is no light left
Ok thanks

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