It’s a water refraction experiment!
Trick and treat your friends and family to an easy, quick, and frightfully fun activity during your festive celebrations.
Draw your favorite characters, shapes, and other creative objects and watch the image disappear when you mix science with a little Halloween magic! You’ll also learn how this activity works and what’s really happening to your image after you dip it into the water.
Gather up the supplies and follow our 5-step guide below to get started:
- Sealable plastic bag (similar to Ziploc)
- OG Halloween Card or a blank drawing sheet
- Permanent marker
- Large bowl
- Optional: scissors
*Safety first: this experiment might require scissors to cut the drawing paper. Please get help from an adult to make sure you complete this trick safely.
WATER REFRACTION ACTIVITY VIDEO
- Print out our OG Halloween Card or draw an image on your sheet of paper.
- Next, place the image inside the sealable bag and close it tightly. You might need to cut the paper with a pair of scissors to fit it inside the bag. Please get help from an adult for added safety.
- Using a permanent marker, carefully trace over the lines of the image.
- Fill up your bowl with water and slowly dip your drawing into the water. (Tip: make sure it’s perfectly vertical)
- Look at the image from an angle (from the top down) and watch as the paper in the bag disappears!
Get extra creative by drawing other Halloween-themed characters and images for more festive fun!
HOW IS THIS HAPPENING?
The answer is LIGHT! Because light helps us see the objects around us… But how?
Light travels through the air, bounces off an object, and then enters our eyes to show us what we’re looking at. So when you’re looking at your drawing paper before putting it in the water, light is traveling through the air, bouncing off of the paper, and entering your eyes all at the same time. That’s why you can see the paper and your amazing drawing. Neat!
But, if you place the paper in the bag and dip it in the water, the light has to travel through the air AND the water before entering your eyes.
NOW THE INTERESTING PART!
If you look at the image at eye level, the light is traveling straight into your eyes after it bounces off the image. That’s why you can see the paper inside the bag under the water from a straight level. But when you start to look at the image from a higher angle, the light begins to bend a little bit once it exits the water instead of traveling in a straight line. This is called refraction.
And the higher you go (looking from the top down), the light begins to bend more and more until it can’t exit the water anymore. It bends so much that it stays underneath the water’s surface and can’t enter your eyes (this is called total internal reflection). And if the light can’t enter your eyes after bouncing off an object, then you can’t see that object. Even if it’s really there. Woah!
This is why you can’t see the paper in the bag when you’re looking at a higher angle. The light that bounces off the paper cannot exit the water and enter your eyes. Which makes it look like it has disappeared. But, the light that bounces off the bag is not completely under the water (yet), so you can still see the outline!