Exploring the Speed of Light in Different Materials

Light is an electromagnetic wave traveling at 300,000 km/s in a vacuum. When it passes through mediums like air, water, or glass, its speed decreases due to absorption and reemission by atoms. This process involves temporary vibrations of electrons, which delay the light's transmission. In water, light travels at 75% of its vacuum speed, in glass at 67%, and in diamond at 41%.

What is the speed of light in a vacuum?

• 300,000 km/s

• 600,000 km/s

• 150,000 km/s

• 450,000 km/s

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What is the term used to refer to the speed of light in a vacuum?

• Speed of waves

• Speed of sound

• Speed of light

• Speed of energy

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What happens to light when it encounters a medium like air or water?

• It changes color

• It speeds up

• It slows down

• It stops

How do atoms in a material affect the speed of light?

• By absorbing and reemitting the light wave energy

• By reflecting the light

• By changing the light's color

• By splitting the light into different wavelengths

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What causes the electrons within atoms to vibrate when light impinges upon them?

• The temperature of the material

• The energy of the incoming light particle

• The elasticity of the nucleus

• The density of the material

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What is the net effect of the absorption and reemission process on the speed of light in a medium?

• It increases the speed of light

• It decreases the speed of light

• It has no effect on the speed of light

• It changes the direction of light

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At what percentage of its speed in a vacuum does light travel through water?

• 50%

• 100%

• 75%

• 90%

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What is the approximate speed of light in glass?

• 300,000 km/s

• 200,000 km/s

• 150,000 km/s

• 250,000 km/s

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How does the speed of light in a diamond compare to its speed in a vacuum?

• It is about 41% of the speed in a vacuum

• It is about 75% of the speed in a vacuum

• It is about 90% of the speed in a vacuum

• It is about 67% of the speed in a vacuum

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What is the speed of light in a diamond?

• 300,000 km/s

• 225,000 km/s

• 200,000 km/s

• 125,000 km/s

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