This disappearing spider trick is simple. Halloween science activity and a great refraction demonstration.
Children can see how the drawing of a spider disappears when water is poured into a glass over the image.
Disappearing spider trick
you will need
glass or glass jar
Drawing of a spider on a sheet of paper.
Water
Instructions
Place a drawing of a spider under the glass.
Slowly fill the glass with water and watch the spider disappear.
Why does it work?
Light (from the sun or artificial light) travels in straight lines, bounces off objects, and enters our eyes, allowing us to see things. Generally, there is little or no refraction of light when it travels through air.
However, when you pour water into the glass or jar, the light from the spider drawing refracts (bends) and does not reach your eyes, so the spider appears to disappear.
More science ideas for Halloween
make a fizzy pumpkin lava lamp.
Try one of my others Spooky Halloween Science Experimentsincluding jumping ghosts, a spooky noise generator or fake blood.
Or how about we give him one of my spooky Halloween STEM Challenges back?
Last updated on October 2, 2024 by Emma Vanstone
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