Light Travels In A Straight Line Flashcards
What is a light-reflecting object?
An object that does not produce light and can only be seen when they reflect light from a light source.
What is a light-radiating object?
An object that radiates light, also known as a light source.
What is a point source of light?
A light source that radiates light only in a specific direction.
What is an umbra?
The dark, clearly distinguishable shadow formed when an object blocks the movement of light rays from a point source of light.
What is a non-point source of light?
A light source that radiates light in multiple directions.
What is a penumbra?
The grey, blurred shadow formed around the umbra when an object blocks the movement of light rays from a non-point source of light.
What determines the colour of an object?
The colour of an object depends on what wavelengths of light it reflects.
What is illuminance?
The amount of light that arrives at a certain surface area, measured in lux (1 lx).
What is white light?
A type of light that contains all of light’s wavelengths.
What is a prism?
An optical device that refracts, reflects, and splits light into a spectrum.
What is visible light?
The wavelength of light that can be distinguished with the naked eye, specifically the wavelengths between 380–740 nm.
slides
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Light has ___ properties and ____ properties
wave-like properties and particle like properties.Light can also be thought of as rays…
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How are shadows caused
When light is blocked by an object, it gets absorbed or reflected away causing a shadows.
Depending on the source of light we can talk about the umbra or the umbra and the penumbra.
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what type of wave is light
transversal
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how much is the speed of light in a vaccuum
close to 299 792 458 m / s
Often we use the estimation 300,000,000 m/s
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what substance does light slow down in?
In air light slows a little bit down. In water or transparent glass/plastic even more.
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how much is the wavelength of visible light
The wavelength of visible light is between 380 - 750 nm
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what is a nanometre
The nano in nanometer or nm is one of the scientific prefixes that we use to denote very big or very small things.
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Formula for calculating the frequency of light
speed = wavelength x frequency or
frequency = speed / wavelength
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how can u seperate the colour from the white light
by using a prism. Colors with a low wavelength (high frequency) refract more.
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what can lasers be used to create
Lasers can be used to produce monochromatic (single-color) light.
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