Polarisation 2D – Malus’ Law Explorer

This simulation visualises the behaviour of light passing through multiple polarising sheets. It demonstrates Malus’ law, showing how transmitted intensity varies with the relative angle between the light’s polarisation direction and the filter’s pass axis, and includes the classic third‑polaroid surprise where a second sheet can restore brightness.

Students can drag individual sheets, rotate them using the on‑screen knobs, and adjust their angles with sliders. Step buttons guide them through a sequence, while Play/Pause, Reset and an Axes toggle control the experiment. A live graph plots the ratio I/I0 as angles change, letting learners see the quantitative relationship in real time.

By interacting with the model, students discover the vector nature of light, how polarisation filters work, and how the intensity follows a cosine‑squared dependence. The activity reinforces concepts from optics curricula and highlights real‑world applications such as sunglasses, LCD displays, and scientific instrumentation.