incidence angle

The incidence angle is the angle at which a wave, like sunlight or a laser beam, strikes a surface relative to a line perpendicular (or normal) to that surface. Imagine shining a flashlight onto a wall; if the beam hits straight on, the angle is 0°, but if it hits at an angle, say 45°, that’s the incidence angle. This angle affects how much energy is transferred, how reflections occur, and how the wave behaves upon contact with the surface. It’s an important concept in fields like optics, remote sensing, and physics to understand how waves interact with surfaces.