A mirror doesn’t ‘see’ or ‘know’ what is in front of it, it just reflects incoming light. In the scenario presented by the TikTok trend, it might seem like the paper is preventing any light that bounces off the smaller object from reaching the mirror, but this is not the case. This is because there isn’t just a single beam striking the mirror and the objects at a 90-degree angle; the light is all around, hitting everything in its path from all angles. As Dr. Sara Webb explains in a video respons