Fun With Rearview Mirrors

Why does an image still appear in a review mirror in a car when you flip the mirror to make it appear that the lights are dim. Why does an image appear when the mirror appears to be reflecting only the back roof of the car?
- Ryan (age 17)
Saskatoon Saskatchewan Canada

Clever, these auto engineers.  The dim image appears because there is pane of clear glass in front of the actual mirror that doesn't move.  The clear glass reflects just a small amount of the incident light and shows a dim image.   The real mirror has been flipped up and then reflects the image of the inside roof in the back seat of the car. 

LeeH

(published on 04/24/2008)