Refraction of Light - Puzzles
1. Why does a stick appear bent when partially immersed in water?
Think about how light changes speed and direction at the water-air boundary.
The bending of light (refraction) causes the stick to appear bent.
2. Why does the depth of a swimming pool appear less than its actual depth?
Consider how light travels from water to air and the refractive index of water.
Light rays bend away from the normal as they move from water to air, making the depth appear less.
3. A coin at the bottom of a glass appears closer than it actually is. Why?
What happens to the path of light when it moves from water to air?
Refraction causes the coin's image to appear at a shallower depth than it is.
4. Why does a prism split white light into its constituent colors?
Different colors of light have different wavelengths and refractive indices.
Dispersion occurs because each color bends by a different amount when passing through the prism.
5. How does the refractive index of a medium affect the bending of light?
Compare the speed of light in different media.
A higher refractive index causes greater bending of light towards the normal.
6. Why does a glass block not disperse light like a prism?
Consider the parallel sides of a glass block.
The parallel sides of the glass block cause the colors to recombine.
7. Why does light travel slower in glass than in air?
Think about the density and refractive index of the materials.
Glass has a higher refractive index and density, reducing the speed of light.
8. What is the apparent depth of a pool with actual depth 2 m and refractive index 1.33?
Use the formula: apparent depth = actual depth / refractive index.
Apparent depth = 2 / 1.33 ≈ 1.5 m.
9. Why does a fish underwater appear closer to the surface to an observer?
Consider the bending of light rays at the water-air interface.
Refraction causes the fish's image to appear closer to the surface.
10. Why do stars appear to twinkle, but planets do not?
Think about the effects of atmospheric refraction.
Atmospheric refraction causes starlight to fluctuate, while planets appear steadier.
