Chapter 12 Review: The Refraction of Light

Chapter 12 Review: The Refraction of Light

Achievement Chart Categories

  • K/U: Knowledge/Understanding

  • T/I: Thinking/Investigation

  • C: Communication

  • A: Application

What Do You Remember?

  1. Procedure for Measuring the Angle of Refraction

    • To measure the angle of refraction, place a light source at a certain angle as it strikes the boundary between two media.

    • Diagram: Include a diagram showing the incident ray, refracted ray, and the normal line at the boundary.

    • Steps:

      • Position the protractor at the boundary

      • Measure the angle of incidence (angle between incident ray and normal)

      • Measure the angle of refraction (angle between refracted ray and normal)

  2. Speed Comparison in Different Materials

    • Light bends towards the normal while entering a medium of greater optical density.

    • If light moves from material A to material B, where material B has a higher index of refraction, light travels slower in material B compared to material A.

    • Concept: Speed of light varies inversely with the index of refraction.

  3. Bending of Light When Slowing Down

    • Light bends towards the normal when it enters a denser medium (i.e., when its speed decreases).

    • Observation: The bending direction depends on the change in speed when transitioning between two materials.

  4. Index of Refraction and Refraction

    • Materials: 1.72, 1.00, 2.30, 1.50

    • Highest index of refraction (2.30) refracts light the most due to its greater optical density relative to others.

  5. Angle of Refraction at Critical Angle

    • At the critical angle, the angle of refraction is 90° and occurs at specific indices of refraction.

  6. Critical Angle Calculation

    • Given a critical angle of 24.5°, the minimum angle of incidence required for total internal reflection is also 24.5° when light travels from a medium with a higher index to a lower index.

    • Calculation Detail: Use Snell's Law to derive related angles.

  7. Apparent Depth Underwater

    • Objects underwater appear shallower than their actual position due to the refraction of light rays as they exit the water into the air.

    • Reality vs. Perception: Apparent depth based on observer's position and angle of view.

  8. Formation of Rainbows

    • Rainbows form through a process of refraction, dispersion, and reflection of sunlight in water droplets.

    • Description: Each droplet acts as a prism separating light into its spectrum.

  9. Light Ray Striking a Window

    • Diagram Task: Copy Figure 1 and draw the path of light ray through glass.

    • Behavior Explanation: Light bends towards the normal when it enters the glass due to a higher index of refraction.

    • Refraction Angle Query: The angle of refraction cannot reach 90° unless total internal reflection is applicable.

  10. Beam of Light Through Two Media

    • Medium Identification: Identify which medium has a higher index of refraction is essential; the medium with the higher index slows light more.

    • Speed Comparison: Within each medium, the speed varies inversely with the index of refraction.

    • Direction Importance: Direction of light does not affect the indices of refraction comparison itself.

  11. Refraction and Equal Speed

    • If light travels at the same speed in air and glass, refraction would not occur as refraction is driven by differences in speed.

  12. Prisms vs. Mirrors

    • Prism Functionality: Prisms can reflect light internally, functioning similarly to mirrors through total internal reflection.

    • Preference for Prisms: Usually termed to maintain beam integrity and minimize loss, prisms allow better manipulation of light.

  13. Rainbow as an Image Type

    • Rainbows are atmospheric optical phenomena that produce a spectrum of light in the sky, typically considered a real image due to physical light dispersion.

  14. Mirage Explanation

    • Shimmering pools on hot asphalt are a result of light refraction due to temperature differences affecting air density.

    • Diagram Requirement: Include a diagram showing how light bends differently at varying temperatures.

What Do You Understand?

  1. Index of Refraction Calculation (Carbon Disulfide)

    • Speed in carbon disulfide: 1.84imes108extm/s1.84 imes 10^8 ext{ m/s}

    • Index formula: n=raccvn = rac{c}{v} where c is the speed of light in vacuum (3.00imes108extm/s3.00 imes 10^8 ext{ m/s}).

    • Calculation: n=rac3.00imes108extm/s1.84imes108extm/s<br>ightarrownext(value)n = rac{3.00 imes 10^8 ext{ m/s}}{1.84 imes 10^8 ext{ m/s}} <br>ightarrow n ext{(value)}

  2. Index of Refraction for Arsenic Trisulfide

    • Given speed: 1.47imes108extm/s1.47 imes 10^8 ext{ m/s}

    • Calculation Method: Same index formula as stated earlier.

  3. Index of Refraction Calculation for Fluorite

    • Given speed in fluorite: 2.10imes108extm/s2.10 imes 10^8 ext{ m/s}

    • Expectation: Lower index value compared to air, which means higher optical density.

  4. Speed in Vegetable Oil

    • Given index of refraction: 1.47.

    • Calculation: Convert index back to speed using v=raccnv = rac{c}{n}, inserting values accordingly.

  5. Speed in Heavy Flint Glass

    • Given index of refraction: 1.65.

    • Calculation remains the same for determining speed.

  6. Speed of Light in Zircon

    • Given index of refraction: 1.92; apply speed calculation formula accordingly.

Create and Evaluate

  1. Fibre-Optic Cable Light Behavior

    • Question Exploration: Light travels in straight lines but can be internally reflected, producing a constantly changing direction in a fibre-optic system.

    • Benefits of Fibre-Optic: Research advantages over copper cables includes higher bandwidth, reduced attenuation, and immunity to electromagnetic interference.

  2. T-chart Comparison of Mirage and Rainbow

    • Mirage: Optical illusion; arises due to refraction through different temperature layers of air.

    • Rainbow: Atmospheric phenomenon; results from sunlight refracting and reflecting in water droplets, creating a spectral display.

  3. Diving for a Puck

    • Explanation: The puck appears higher due to refraction; your brother should dive at an angle towards the puck's perceived position to retrieve it effectively.

    • Presentation Methods: Oral, written, or diagrams should convey this understanding.

  4. Opinion on Invisibility Cloaks

    • Science and Technology Evaluation: Not always beneficial; potential of misuse exists but beneficial applications across fields could provide security or concealment in various contexts.

    • Potential Applications Evaluation: Analyzing military vs. civilian uses can provide clear benefits or hazards attached to utilization.

Reflect on Your Learning

  1. Greater Understanding of Nature

    • Personal Insight: Knowledge of refraction allows for better interpretation of optical events like mirages; enhances sensory perception of common events such as shimmering pools or rainbows.

Web Connections

  1. Historical Speed of Light Measurement

    • Research historical methods such as Foucault's rotating mirror experiment and others who have attempted to measure light speed.

    • Prepare summarized findings either orally or in written form.

  2. Secondary and Tertiary Rainbows

    • Investigate how multiple rainbows are produced, focusing on interactions of light through water droplets, diagramming your findings.

  3. Rear-View Mirror Functionality

    • Research and explain how the dual-functioning rear-view mirror minimizes glare at night yet maintains visibility, including accompanying diagrams.

End of Chapter 12 Review