Question 1: Refraction is the bending of light as it passes from one transparent medium to another due to a change in its speed. This phenomenon occurs because light travels at different speeds in different materials, governed by the material's refractive index.

Answer: Refraction is the bending of light when it passes between different media because of a change in its speed.

Question 1: What is the name of the law that relates the angles of incidence and refraction when light passes between two media?

Answer: Snell's Law

Question 2: Explain why light bends towards the normal when passing from air into a denser medium like glass.

Answer: Light bends towards the normal because it slows down in the denser medium, causing a change in direction according to Snell's Law.

Question 1: A ray of light passes from air (refractive index n=1.00) into glass (n=1.50) with an incident angle of 30°. Calculate the angle of refraction within the glass.

Answer: 19.5°

Question 2: A laser beam passes through a rectangular prism of acrylic (refractive index 1.49). If the incident angle in air is 45°, what is the critical angle for total internal reflection inside the acrylic?

Answer: 42.2°

Question 1: Describe the key safety precautions to consider when conducting an experiment involving refraction of light with lasers.

Answer: Wear safety goggles, avoid direct eye contact with laser beams, and ensure the laser is properly secured to prevent accidental exposure.

Question 2: Identify the variables that can be changed in a refraction experiment and explain how they affect the outcome.

Answer: Variables include the angle of incidence, the refractive index of the medium, and the wavelength of light. Changing the angle affects the refraction angle; different media alter the bending due to their refractive indices; wavelength variations can cause dispersion effects.

Question 1: A student measures the angle of incidence as 40° when a light ray passes from air into a liquid with an unknown refractive index. The angle of refraction is recorded as 25°. Calculate the refractive index of the liquid.

Answer: 1.60

Question 1: Explain how the phenomenon of refraction is utilised in fibre optic technology and discuss its advantages in telecommunications.

Answer: Refraction allows light signals to be guided through thin flexible fibres by total internal reflection, which occurs when light hits the boundary at angles greater than the critical angle. This technology enables high-speed, low-loss data transmission over long distances, supporting global telecommunications infrastructure.

Question 1: Provide an example of how refraction is used in the design of corrective lenses for eye conditions.

Answer: Corrective lenses use refraction to bend light rays so they focus properly on the retina, correcting conditions like short-sightedness and long-sightedness.