Refraction: Practice Questions

In the study of refraction, what does the 'normal' refer to?

When a straight spoon is partially immersed in a glass of water, it appears bent or broken at the water surface. This phenomenon is caused by:

A small light source is placed at the bottom of a pool of water. A person is looking at the water surface from air at a large angle. Due to refraction, the light ray from the source appears to originate from a different position. If the angle of incidence of a light ray at the water-air interface from the light source gradually increases, what phenomenon will eventually occur?

When a light ray travels from air into a glass block at an angle, it bends. Which of the following stays constant during this process?

A light ray travels from water (a denser medium) into air (a less dense medium). Which of the following statements correctly describes the path of the light ray?

When a light ray travels from an optically less dense medium (like air) into an optically denser medium (like water) at an angle to the normal, how does the path of the light ray change?

State the two necessary conditions that must be satisfied for a light ray travelling across a boundary between two transparent media to undergo Total Internal Reflection (TIR).

What is the primary physical cause for the phenomenon of refraction when light travels from one transparent medium (like air) into another (like glass)?

A student observes a fish swimming in a pond. To the student, the fish appears to be at a depth of 0.75 m below the water surface. However, the student knows that the actual position of the fish is deeper due to the refraction of light. The refractive index of water is 1.33.

(a) Explain why the fish appears shallower than its actual depth when viewed from air.

(b) Use the relationship between refractive index, actual depth, and apparent depth to calculate the actual depth of the fish in meters. (Give your answer to 2 decimal places.)

(c) If the student looks directly downwards at the fish (at an angle of incidence of \( 0^\circ \)), would the fish still appear shallower? Briefly explain your answer.

A student is investigating the path of a monochromatic light ray as it passes through a boundary between two transparent liquids, Liquid P and Liquid Q. The refractive index of Liquid P is given as \(n_P = 1.25\) and the refractive index of Liquid Q is \(n_Q = 1.50\).

(a) The light ray originates in Liquid P and strikes the boundary with Liquid Q at an angle of incidence of \(50^\circ\). Calculate the angle of refraction in Liquid Q. (Give your answer to one decimal place. Assume \(\sin(50^\circ) \approx 0.766\)).

(b) Define the term optical density in relation to light travel and refractive index. Based on your definition, identify which liquid (P or Q) is optically denser.

(c) If the experiment were reversed, and the light traveled from Liquid Q back into Liquid P at the same boundary, how would the direction of the refracted ray compare to the normal? Explain your reasoning.