Reflect on this

Why is it that your image in a mirror is reversed left to right but not reversed up and down? For example, if you raise your left arm, the person you can see in the mirror raises their right arm. But when you point up, the person in the mirror does not point down! 

Test your understanding of reflection by imagining a few other scenarios.

·      What would you see in the mirror if you stood on your head in front of a mirror with a paper bag over your left foot?

·      What would you see if you lay on your right side facing the mirror and pointed upwards with your left arm?

·      What do you see when you are driving on the left in a right-hand drive car and you look in the rear-view mirror at the car behind. Do you see someone driving on the right in a left-hand drive car?

·      Now imagine going up a hill and looking down at a lake surrounded by trees. What would you notice about the reflections of the trees in the lake?

So, what do you think? Is it true to say that mirrors reverse images left to right but not up and down?