“When a pencil is placed in a glass of water, why does it look like the pencil is bent?” If you’ve ever wondered about this, then you’re in for a treat! In this blog post, we’ll explore the broken pencil illusion – a fun and easy science experiment that demonstrates the phenomenon of light refraction. Not only is this a great activity for kids, but it’s also a great way to teach them about the basics of physics. So let’s get started!
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WHAT YOU’LL NEED
- A pencil
- 1 clear glass cup
- water
What happens when you put a pencil in water?
Fill the glass with water up to two thirds of the way.
Then place the pencil in the water at an angle and look at the pencil from the side of the clear glass.
You should see that the pencil appears to be broken in two, even though it isn’t!
WHY DOES A PENCIL LOOK BROKEN / BEND IN WATER
The pencil looks broken or bend in water because of light refraction. When light passes from one medium (like air) into another medium (like water), the light waves bend. This happens because light travels through different materials, or mediums, at different speeds.
In this experiment, light first travels through the air – which is easy to move through – and then through the water, where it slows down. This change in speed causes the light to bend, or refract, meaning that the part of the pencil that is in the water will appear shifted.
This bending of light waves in water is what causes the broken pencil illusion. What do you think will happen if you put a pencil in oil instead of water?
RELATED POST : VALENTINE THEMED SCIENCE EXPERIMENT ON REFRACTION OF LIGHT
WHAT IS THE DIFFERENCE BETWEEN REFLECTION AND REFRACTION
Reflection occurs when light bounces off a medium and returns back to the originating medium. While refraction is the process of light waves changing direction as they pass through one medium to another, resulting in their bending.
How is refraction of light used in everyday life?
Those who have worn contacts or glasses know how light refraction enhances eyesight. Did you ever wonder what causes rainbows to form? This principle of light refraction is also used in many everyday items and devices. Due to the bending or refraction of light, we can enlarge objects using magnifying glasses or view far-off objects through binoculars.
Examples of objects that refract light
- Prism
- Ice crystals
- Twinkling stars
- Lens
- Binoculars
- Magnifying glass
- Human Eye
- Contact lenses or glasses
What material bends the light most ?
Materials with a high refractive index bend light the most, such as diamond. Diamonds both reflect and refract, which explains why they glitter so brilliantly. Diamonds are cut to have many flat sides, or facets.
You can have fun with teaching kids about how light moves and bends in various materials using just a few common household items ! This easy science experiment is a great way to introduce them to physics concepts like reflection and refraction while also sparking their curiosity about light and its behavior. Give it a try today !
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