Test your understanding of refraction, its laws, and the behavior of light through glass slabs and prisms!
Puzzle 1: What happens to the direction of light when it passes from air into a glass slab?
Hint: Think about the change in speed of light.
Answer: The light bends towards the normal because it slows down in the denser medium.
Puzzle 2: Why does a ray of light bend when it enters a different medium?
Hint: Consider the change in the speed of light.
Answer: A ray of light bends because the speed of light changes when moving between media with different optical densities.
Puzzle 3: What is the angle of refraction if a ray of light enters a glass slab perpendicularly?
Hint: What happens when the angle of incidence is 0°?
Answer: The angle of refraction is 0° because the light passes straight without bending.
Puzzle 4: Why does a ray of light passing through a glass slab emerge parallel to the incident ray?
Hint: Think about lateral displacement.
Answer: The ray emerges parallel because the refraction at the two surfaces cancels out the angular change, causing only lateral displacement.
Puzzle 5: State the first law of refraction.
Hint: It's about the incident ray, refracted ray, and the normal.
Answer: The incident ray, refracted ray, and the normal all lie in the same plane.
Puzzle 6: State Snell's law of refraction.
Hint: It's a relationship between angles and refractive indices.
Answer: Snell's law states that n_1 \sin i = n_2 \sin r, where n_1 and n_2 are the refractive indices of the two media, and i and r are the angles of incidence and refraction, respectively.
Puzzle 7: Why does a prism split white light into its constituent colors?
Hint: Think about the dependence of refraction on wavelength.
Answer: The prism splits white light because different wavelengths of light refract at different angles, causing dispersion.
Puzzle 8: What is lateral displacement in a glass slab?
Hint: It's related to the parallel shift of the ray.
Answer: Lateral displacement is the perpendicular distance between the incident ray and the emergent ray after passing through a glass slab.
Puzzle 9: What happens to the speed of light when it moves from a rarer to a denser medium?
Hint: Consider the optical density of the medium.
Answer: The speed of light decreases when moving from a rarer to a denser medium.
Puzzle 10: Why does a pencil appear bent when placed in a glass of water?
Hint: It’s due to the bending of light.
Answer: The pencil appears bent because light refracts at the interface between water and air, changing its direction.