4.3 Reflection and Refraction

• Reflection occurs when a wave encounters a boundary between two different media
• What is the angle of incidence?

  Angle between incident wave and normal
• Match the term with its definition:

  Incident wave ↔️ The wave approaching the boundary

  Reflected wave ↔️ The wave bouncing back

  Angle of incidence (θi) ↔️ Angle between incident wave and normal

  Angle of reflection (θr) ↔️ Angle between reflected wave and normal
• The angle of incidence is always equal to the angle of reflection.


  True
• What is the mathematical statement of the law of reflection?

  $\theta_{i} =$$\theta_{r}$
• The incident ray, reflected ray, and normal all lie in the same plane.


  True
• What happens to a wave during refraction?

  Changes direction
• Steps to describe Snell's law

  1️⃣ Define the refractive indices (n1 and n2)

  2️⃣ Identify the angle of incidence (θi)

  3️⃣ Identify the angle of refraction (θr)

  4️⃣ Apply the formula: $n_{1} \sin \theta_{i} =$$n_{2} \sin \theta_{r}$
• n1 in Snell's law represents the refractive index of the first medium.


  True
• The angle of incidence in Snell's law is denoted by θi.


  True
• Reflection occurs when a wave bounces back into the original medium after encountering a boundary.

  True
• In reflection, the incident ray, reflected ray, and normal all lie in the same plane.


  True
• Order the key components in a diagram illustrating the laws of reflection:

  1️⃣ Incident ray

  2️⃣ Reflected ray

  3️⃣ Normal

  4️⃣ Surface
• Refraction occurs when a wave changes direction as it passes from one medium to another.


  True
• Snell's law is used to design lenses in optical devices.


  True
• Snell's Law is used in optics to design lenses and prisms
• Total internal reflection is the principle behind the operation of optical fibers
• What is an incident wave?

  The wave approaching the boundary
• What is the angle of reflection?

  Angle between reflected wave and normal
• What are the two laws of reflection?

  θi = θr and same plane
• What is the definition of the normal in reflection?

  Line perpendicular to the surface
• The angle of incidence is equal to the angle of reflection.


  True
• Refraction alters both the speed and wavelength of a wave.


  True
• Match the term with its definition:

  Refracted wave ↔️ Wave that changes direction

  Angle of refraction (θr) ↔️ Angle between refracted wave and normal

  Snell's law ↔️ $n_{1} \sin \theta_{i} =$$n_{2} \sin \theta_{r}$
• What is Snell's law used to describe?

  Wave refraction
• What does n1 represent in Snell's law?

  Refractive index of the first medium
• Match the term with its definition:

  Incident wave ↔️ Wave approaching the boundary

  Reflected wave ↔️ Wave bouncing back from the boundary

  Angle of incidence (θi) ↔️ Angle between incident wave and normal

  Angle of reflection (θr) ↔️ Angle between reflected wave and normal
• What is the definition of reflection in wave phenomena?

  Wave bounces back from a boundary
• What is the primary cause of wave refraction?

  Change in refractive index
• In what field is Snell's law commonly applied?

  Optics
• What is the formula for Snell's Law?

  $n_{1} \sin \theta_{i} =$$n_{2} \sin \theta_{r}$
• What happens when light exceeds the critical angle?

  Total internal reflection
• The critical angle depends on the refractive indices of both media.


  True
• What is the definition of reflection of waves?

  Waves bounce off boundaries
• What is a reflected wave?

  The wave bouncing back
• The angle of incidence is equal to the angle of reflection.


  True
• The incident ray, reflected ray, and normal all lie in the same plane
• The incident ray, reflected ray, and normal lie in the same plane
• The angle of incidence is equal to the angle of reflection
• Match the term with its definition:

  Angle of Incidence (θi) ↔️ Angle between incident ray and normal

  Angle of Reflection (θr) ↔️ Angle between reflected ray and normal

  Normal ↔️ Line perpendicular to the surface