⚛️ Physics Quiz 14: Light, Reflection, and Refraction

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⚛️ Physics · Quiz 014

Extend the wave foundation of PHYS-010 into geometric optics without yet introducing lens-image calculations.

Learning goalApply reflection, refractive index, Snell's law, and total internal reflection while preserving frequency across stationary interfaces.

  • 5 questions
  • Foundation
  • Explanations after finishing
Answered 0/5
FoundationFor specular reflection from a stationary mirror, how are the angle of incidence and angle of reflection related when both are measured from the surface normal?
Need a small nudge?

Use the law of reflection and measure both angles from the normal, not from the surface.

UnderstandingA light ray passes from air into transparent glass with a larger refractive index. For a nonzero incident angle below 90 degrees, which statement is correct?
Need a small nudge?

A larger refractive index means a lower light speed. Then apply Snell's law.

ApplicationLight travels from air (n1 = 1.00) into glass (n2 = 1.50) at an incidence angle of 30.0 degrees from the normal. What is the refracted angle?
Need a small nudge?

Use n1 sin theta1 = n2 sin theta2.

InterpretationWhich condition is required for total internal reflection at a boundary between two transparent media?
Need a small nudge?

Total internal reflection occurs only when refraction would otherwise bend the ray far enough away from the normal to reach 90 degrees.

ConnectionA monochromatic light wave enters stationary glass of refractive index 1.50 from air. Which combination correctly describes the light in the glass, compared with air?
Need a small nudge?

At a stationary interface the source frequency is preserved. Use v = c/n and v = f lambda.

Further reading

  • For Question 1 on “specular reflection”, the section “🔍 Light, surfaces, and the law of reflection” adds this context: “This leads to a useful distinction between specular and diffuse reflection. Specular reflection occurs when a surface is smooth enough that its height variations are small compared with the wavelength of visible light, which is about 0.000016 inches to 0.000028 inches (about 400 to 700 nanometers).” 🌟 When Light Learns to Answer Back: The Quiet Science of Mirrors

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