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VladimirAG [237]

3 years ago

7

In a perfect vacuum, light waves travel at 300,000 kilometers every second. When light waves travel through materials, such as a

ir, they
A.speed up

B.slow down

C.increase in amplitude

D.Heat up

2 answers:

ruslelena [56]3 years ago

3 0

They slow down so the answer is B

yanalaym [24]3 years ago

3 0

c = speed of light in vacuum = 300,000 kilometers/second

n = index of refraction of material

v = speed of light in the material

Speed of light in a given material is given as

v = C/n

v = 300,000/n

for air, the value of index of refraction "n" is slightly greater, hence the speed of light in air is smaller than 300,000 kilometers/second. hence the light waves slow down.

so correct choice is

B.slow down

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jeyben [28]

<u>Answer :</u>

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3 years ago

Read 2 more answers