Physics Uncovered on Instagram: "When the anchor plunges into the ocean, it’s gravity in action — Earth pulling every object toward its center. The deeper it sinks, the stronger the pressure, the denser the water, and the slower its fall becomes. But in the same clip, notice how light bends as it passes from air into water. That’s refraction — caused by a change in the light’s speed as it moves through a denser medium. The light path curves, just as the anchor’s descent is curved by the pull of

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