Light and Optics Quiz

What is the speed of light in a vacuum?

• 3 × 10⁸ m/s
• 2 × 10⁸ m/s
• 670 million miles per hour
• 7 times Earth's circumference per second

Which color of visible light has the longest wavelength?

• Violet
• Green
• Red
• Blue

What is the relationship between wavelength (λ), frequency (f), and the speed of light (c)?

• λf = c
• λ = cf
• f = λc
• c = λ/f

What happens to the speed of light when it enters a medium other than vacuum?

• It increases
• It decreases
• It remains constant
• It becomes zero

What is the index of refraction (n) of a vacuum?

• 0
• 1
• 1.5
• 3

In the law of reflection, what is the relationship between the angle of incidence and the angle of reflection?

• They are equal
• The angle of incidence is twice the angle of reflection
• The angle of reflection is twice the angle of incidence
• They are complementary

What is the phenomenon called when light bends as it passes from one medium to another?

• Reflection
• Refraction
• Diffraction
• Interference

Which equation represents Snell's Law?

• n₁ sin θ₁ = n₂ sin θ₂
• n₁ cos θ₁ = n₂ cos θ₂
• n₁ tan θ₁ = n₂ tan θ₂
• n₁ θ₁ = n₂ θ₂

If light travels from air (n = 1) to glass (n = 1.5), what happens to its speed?

• It increases by 1.5 times
• It decreases by 1.5 times
• It remains the same
• It becomes zero

What type of lens causes parallel light rays to converge?

• Convex lens
• Concave lens
• Plane lens
• Diverging lens