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In this video, we will be observing how materials with similar refractive indices can be used to make one of the objects seem invisible!

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This eyedropper is made of glass.

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The liquid in the bottle has a very similar refractive index to that of the glass used in making the eyedropper.

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This means that both the glass and the liquid distort light by bending light rays in a very similar way.

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This fact can result in a rather surprising phenomenon.

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When we lower the eyedropper into the bottle full of liquid, we can still see it.

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This is because the eyedropper is currently full of air.

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Air has a different refractive index to that of the glass that forms the eyedropper, so it bends light slightly differently.

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But let’s see what happens when we fill the eyedropper with the liquid in the bottle.