Answer to Question #196955 in Physics for Hahahaha

Question

Jeff, who is 6.0 f tall, stands in front of plane mirror. What is the shortest plane mirror that Jeff can use to see his full-sized image?

With solution

Answer 1

A person looks at his image in the mirror as in a "window". Straight lines drawn from the human eye to the extreme points of the image must pass through the mirror. Therefore, the height of the mirror should be not less than half the height of a person, and its upper edge - not lower than the human head. So,

$h_{min}=6/2=3\ (ft)$