Física: Eletromagnetismo, Ótica e Termodinâmica - Prática 01

Scientific concepts / nature phenomena presented

Electromagnetism / optics practical context

• The video is a lab/practical session focused on optical refraction (within a broader course that also includes electromagnetism and thermodynamics, though only optics is treated here).

Refraction and Snell’s law

• The core activity uses Snell’s law (also called the law of refraction) to find the refractive index of two “mystery” materials:
  • Mystery Medium A
  • Mystery Medium B
• Refraction geometry uses angles measured with respect to the normal.
• The simulator involves:
  • Setting an angle of incidence
  • Setting/observing an angle of refraction
  • Solving for the refractive index (n) of the unknown medium (with air treated as (n \approx 1)).

Wave behavior in refraction (dispersion-related reasoning)

• The video instructs analyzing how wave properties change after refraction:
  • Wavelength
  • Frequency
  • Wave speed
• Example wavelengths mentioned (associated with visible light colors):
  • 400 nm (violet region)
  • 600 nm
  • 700 nm
• The task is to identify trends, such as:
  • Whether wavelength increases or decreases
  • Whether wave speed changes, and how
  • How (or whether) the refracted wave’s characteristics vary

Angle of deviation

• A final part focuses on the angle of deviation from refraction through a prism-like setup:
  • Given angle of incidence = 45°
  • And angle of refraction = 17°
• The exercise asks to determine the angle of deviation.

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Methodology / procedure outlined (from the simulator instructions)

Access and configure the PetColor software

1. Go to PetColor website: PetColor.edu
2. Use the Physics section
3. Filter simulations to keep only Light Deviation
   • Remove other categories such as:
     • waves/sound
     • work/heat/temperature
     • quantum
     • electricity

Practice 1: Determine refractive index of Mystery Medium A

• Set:
  • Mystery Medium A as the unknown material
  • Angle of incidence (i = 45^\circ)
  • Angle of refraction (r = 17^\circ)
• Apply Snell’s law to solve for the refractive index (n_A)
  • Air is assumed (n \approx 1)

Practice 2: Determine refractive index of Mystery Medium B

• Set:
  • Angle of incidence (i = 44^\circ)
  • Angle of refraction (r = 30^\circ)
• Apply Snell’s law again to solve for the refractive index (n_B)

Analyze wave properties during refraction

• Select the wave in the simulator.
• Repeat observation for:
  • 400 nm, then 600 nm, then 700 nm
• For each wavelength, examine changes in:
  • wavelength
  • frequency
  • wave speed
• Observe whether the refracted wave’s characteristics change.

Compute/observe angle of deviation

• Using the earlier incidence/refraction pair (45° → 17°), determine the angle of deviation.

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Researchers / sources featured (as named in the subtitles)

• PetColor (software / educational platform)
• Google (referenced as a starting point for searching the site)
• No individual researchers or scientific authors are explicitly named in the subtitles.