Hooked on Science: Toilet paper tube x-ray

Materials

* Toilet paper tube

Instructions

STEP 1: Using your right hand, hold the toilet paper tube against your right eye, so you can see through the tube.

STEP 2: Keep both eyes open and focus on any object in the room.

STEP 3: Hold your left hand in front of your face, with your palm facing your left eye. Place the edge of your left hand, the pinkie-finger side, so it is touching near the end of the toilet paper tube and observe.

Explanation

As you peek through the toilet paper tube, a hole appears in your left hand. This is an optical illusion caused by your brain taking what your right eye observes, and what your left eye observes, and putting the images together to create a picture. This confuses your brain and creates a picture with a hole in your hand.

Jason Lindsey is a science outreach educator with Hooked on Science Check out his website hookedonscience.org for webcasts and experiments.