Visualise polarisation and Malus's law in 3D

Direct answer

Watch the electric field of light through two or three polarisers in 3D, verify Malus's law and find the Brewster angle.

Unpolarised light vibrates in all directions; a polariser keeps only one. Each later polariser passes cos² of the angle between it and the light's direction.

Simulation

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Polarisation and Malus's Law in 3D

Wave optics

Set-up Two polarisers

Analyser angle θ (°) 30°

Middle polariser φ (°) 45°

Refractive index n (Brewster) 1.5

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What's happening? Unpolarised light vibrates in all directions; a polariser keeps only one. Each later polariser passes cos² of the angle between it and the light's direction.

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Where it is in NCERT: Class 12 Physics Part II, “Wave Optics” (Huygens Principle, Refraction and Reflection of Plane Waves using Huygens Principle, Coherent and Incoherent Addition of Waves, Interference of Light Waves and Young's Experiment) · ncert.nic.in
Topic notes and formulas: Wave Optics
Printable formula sheet
Chapter-wise JEE Main PYQs (11)