Why is a laser beam visible when laser light travels in one direction?
Context The question addresses the apparent contradiction between the unidirectional nature of laser light and the visibility of the laser beam itself. It explores how light, which is emitted in a straight line from a laser, can be perceived from various angles, enabling us to see the entire path of the beam. The question arises from the common observation of laser beams, especially in dusty or smoky environments, prompting curiosity about the underlying physics that makes the beam visible. Simple Answer Laser light is super focused, going mostly in one direction. Tiny stuff like dust or water in the air bumps into the laser light. When the light bumps into these things, it scatters in all directions. Some of this scattered light then travels to your eyes. That's why you see the laser beam, even though the light started in one direction. Detailed Answer The visibility of a laser beam, despite its highly directional nature, stems from a phenomenon known as light scattering. In a per...