6.3.2 Refraction of Waves

• What is refraction?

  Bending of waves
• Light waves speed up when they enter a denser medium.

  False
• Light waves bend towards the normal
• Do sound waves speed up or slow down in denser mediums?

  Speed up
• Sound waves bend away from the normal in denser mediums.
• What law governs the relationship between the angles of incidence and refraction?

  Snell's Law
• Snell's Law states that n_{1} \sin \theta_{1} = n_{2} \sin \theta_{2}</latex>, where $\theta_{1}$ is the angle of incidence
• Match the property of waves with their behavior in denser mediums:

  Light Waves ↔️ Bends Towards Normal

  Sound Waves ↔️ Bends Away from Normal
• What does Snell's Law describe?

  Refraction of waves
• Snell's Law is only applicable for light waves.

  False
• What is the refractive index of a medium a measure of?

  Light slowing down
• The refractive index is calculated as $n =$$\frac{c}{v}$, where c</latex> is the speed of light in a vacuum
• Match the factor affecting refractive index with its effect:

  Wavelength/Frequency ↔️ Higher frequency = Higher index

  Density ↔️ Higher density = Higher index

  Temperature ↔️ Higher temperature = Lower index
• Shorter wavelengths of light experience less bending in a medium.

  False
• What happens to the refractive index as the density of a medium increases?

  Increases
• Increasing temperature typically decreases the density of a medium, lowering its refractive index.
• What effect does a denser medium have on the refractive index?

  Increases the refractive index
• Typically, increasing temperature decreases density and lowers the refractive index.
• Higher frequency light interacts more with particles in a medium, leading to a higher refractive index.
• Match the factor with its effect on the refractive index:

  Wavelength/Frequency ↔️ Higher frequency = Higher index

  Density ↔️ Higher density = Higher index

  Temperature ↔️ Higher temperature = Lower index
• Steps to understand the factors affecting refractive index:

  1️⃣ Identify the factors

  2️⃣ Explain the effect of each factor

  3️⃣ Provide examples for each effect
• What is the refractive index defined as?

  $n =$$\frac{c}{v}$
• Different wavelengths of light have different refractive indices in a medium.
• Light waves bend towards the normal when entering a denser medium.
• What happens to sound waves when they enter a denser medium?

  Speed up and bend away
• Snell's Law relates the refractive indices and angles of incidence and refraction.
• Match the wave type with its behavior in a denser medium:

  Light Waves ↔️ Bend Towards Normal

  Sound Waves ↔️ Bend Away From Normal
• Snell's Law is given by the equation: $n_{1} \sin \theta_{1} =$$n_{2} \sin \theta_{2}$.
• In Snell's Law, what does $n_{1}$ represent?


  Refractive index of medium 1
• In Snell's Law, what does $\theta_{2}$ represent?


  Angle of refraction
• What does Snell's Law describe the relationship between?

  Refractive indices and angles
• Snell's Law is given by the equation n_{1} \sin \theta_{1} = n_{2} \sin \theta_{2}
• The refractive index $n_{1}$ in Snell's Law refers to medium 1.
• What does the variable $\theta_{1}$ represent in Snell's Law?


  Angle of incidence
• The refractive index $n_{2}$ in Snell's Law refers to the refractive index of medium 2.
• What is the variable \theta_{2}</latex> in Snell's Law defined as?

  Angle of refraction
• The refractive index of air is approximately 1.00.
• If light travels from air into glass at an incidence angle of $30^\circ$, the refractive index of glass is $1.50$, and the refractive index of air is $1.00$, the angle of refraction is 19.5^\circ.
• What does Snell's Law describe the relationship between?

  Refractive indices and angles
• Snell's Law is given by the equation: $n_{1} \sin \theta_{1} =$$n_{2} \sin \theta_{2}$