Light Travels In A Straight Line

Question 1

What is a light-reflecting object?

Answer 1

An object that does not produce light and can only be seen when they reflect light from a light source.

Question 2

What is a light-radiating object?

Answer 2

An object that radiates light, also known as a light source.

Question 3

What is a point source of light?

Answer 3

A light source that radiates light only in a specific direction.

Question 4

What is an umbra?

Answer 4

The dark, clearly distinguishable shadow formed when an object blocks the movement of light rays from a point source of light.

Question 5

What is a non-point source of light?

Answer 5

A light source that radiates light in multiple directions.

Question 6

What is a penumbra?

Answer 6

The grey, blurred shadow formed around the umbra when an object blocks the movement of light rays from a non-point source of light.

Question 7

What determines the colour of an object?

Answer 7

The colour of an object depends on what wavelengths of light it reflects.

Question 8

What is illuminance?

Answer 8

The amount of light that arrives at a certain surface area, measured in lux (1 lx).

Question 9

What is white light?

Answer 9

A type of light that contains all of light’s wavelengths.

Question 10

What is a prism?

Answer 10

An optical device that refracts, reflects, and splits light into a spectrum.

Question 11

What is visible light?

Answer 11

The wavelength of light that can be distinguished with the naked eye, specifically the wavelengths between 380–740 nm.

Question 12

slides

Answer 12

31,32,33-42

Question 13

Light has ___ properties and ____ properties

Answer 13

wave-like properties and particle like properties.Light can also be thought of as rays…
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Question 14

How are shadows caused

Answer 14

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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Question 15

what type of wave is light

Answer 15

transversal
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Question 16

how much is the speed of light in a vaccuum

Answer 16

close to 299 792 458 m / s
Often we use the estimation 300,000,000 m/s
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Question 17

what substance does light slow down in?

Answer 17

In air light slows a little bit down. In water or transparent glass/plastic even more.
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Question 18

how much is the wavelength of visible light

Answer 18

The wavelength of visible light is between 380 - 750 nm
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Question 19

what is a nanometre

Answer 19

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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Question 20

Formula for calculating the frequency of light

Answer 20

speed = wavelength x frequency or
frequency = speed / wavelength
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Question 21

how can u seperate the colour from the white light

Answer 21

by using a prism. Colors with a low wavelength (high frequency) refract more.
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Question 22

what can lasers be used to create

Answer 22

Lasers can be used to produce monochromatic (single-color) light.
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