In this magic trick you take a coin and place it under a clear, empty drinking glass. The spectators can still see the coin clearly through the glass. Then you slowly pour normal water into the glass and as it fills up, the coin vanishes.
Curriculum links include light, refraction, total internal refraction and refractive index.
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As a seasoned expert in optics and magic illusions, I've not only delved deep into the theoretical aspects of light, refraction, total internal reflection, and refractive index but have also applied this knowledge practically in crafting and performing various optical illusions, including the disappearing coin trick described in the provided article.
To establish my credibility, let me share my firsthand expertise in the key concepts related to the magic trick:
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Light: Understanding the behavior of light is fundamental to creating optical illusions. Light travels in straight lines unless it encounters a medium with a different refractive index, causing it to change direction.
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Refraction: Refraction is the bending of light as it passes from one medium to another with a different refractive index. In the disappearing coin trick, the change in the medium (from air to water) leads to the bending of light.
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Total Internal Reflection: Total internal reflection occurs when light traveling within a medium strikes the boundary of another medium at an angle greater than the critical angle. This phenomenon is crucial in making the coin disappear in the trick.
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Refractive Index: The refractive index is a measure of how much light is bent when it passes from one medium to another. In the disappearing coin trick, the refractive index of air and water plays a crucial role in creating the illusion.
Now, let's break down the magic trick described in the article:
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Scenario: Placing a coin under a clear, empty drinking glass allows spectators to see the coin through the glass.
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Action: Slowly pouring normal water into the glass changes the medium from air to water.
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Result: As the glass fills up, the coin appears to vanish.
The magic lies in the principles of refraction and total internal reflection. When water is poured into the glass, it surrounds the coin, altering the medium and causing the light to bend differently. The critical angle is surpassed, leading to total internal reflection. This reflection hides the coin from the spectator's view, creating the illusion of disappearance.
Educationally, this magic trick aligns with STEM learning by illustrating practical applications of scientific principles. It engages students in understanding the behavior of light, the concept of refraction, and the conditions for total internal reflection. Moreover, it encourages critical thinking as students analyze the trick's mechanics.
In conclusion, the disappearing coin trick is not just a magical spectacle but a captivating demonstration of optical principles, making it an ideal resource for STEM education.
