AP Physics 2: Algebra-Based Practice Quiz: Refraction
Written by AP Content Team, Verified for 2026 AP Exams, Last updated: May 2026
Test your understanding with short quizzes. This quiz has 12 questions to check your progress.
Question 1 of 12
All Questions (12)
A) The bending of light as it is absorbed by a medium.
B) The change in direction of a light ray as it passes from one medium to another.
C) The reflection of light off a smooth, polished surface.
D) The splitting of light into its constituent colors.
Correct Answer: B
According to the provided content, 'Refraction is the change in direction of a light ray as the ray passes from one medium into another.' This directly matches option B.
A) A change in the frequency of light.
B) A change in the intensity of light.
C) A change in the speed of light.
D) A change in the polarization of light.
Correct Answer: C
The provided text states that 'Refraction is a result of the speed of light changing when light enters a new medium.' This indicates that the change in speed is the primary cause.
A) The speed in glass is greater than c.
B) The speed in glass is less than c.
C) The speed in glass is equal to c.
D) The relationship cannot be determined without knowing the angle of incidence.
Correct Answer: B
The index of refraction is defined as n = c/v. Since the index of refraction for any medium other than a vacuum is greater than 1, the speed of light in the medium (v) must be less than the speed of light in a vacuum (c).
A) It will bend toward the normal.
B) It will bend away from the normal.
C) It will not bend at all.
D) It will be totally internally reflected.
Correct Answer: A
According to Snell's Law, n₁sinθ₁ = n₂sinθ₂. If n₂ > n₁, then for the equality to hold, sinθ₂ must be less than sinθ₁. This means the angle of refraction (θ₂) is smaller than the angle of incidence (θ₁), so the ray bends toward the normal.
A) When light passes from a medium with a higher index of refraction to one with a lower index of refraction.
B) When light passes from a medium with a lower index of refraction to one with a higher index of refraction.
C) Whenever light strikes the boundary between two media at a 90-degree angle.
D) Whenever the two media have the same index of refraction.
Correct Answer: A
The provided content explicitly states that 'Total internal reflection may occur when light passes from one medium into another medium with a lower index of refraction.' This corresponds to the condition n₁ > n₂.
A) 30°
B) 45°
C) 60°
D) 90°
Correct Answer: A
The critical angle (θc) is found using the equation sin(θc) = n₂/n₁. Plugging in the given values: sin(θc) = 1.0 / 2.0 = 0.5. The angle whose sine is 0.5 is 30°.
A) 0.50
B) 1.50
C) 1.73 (√3)
D) 2.00
Correct Answer: C
Using Snell's Law, n₁sinθ₁ = n₂sinθ₂. We can solve for n₂: n₂ = n₁(sinθ₁/sinθ₂). Plugging in the values: n₂ = 1.0 * (sin(60°)/sin(30°)) = (√3/2) / (1/2) = √3 ≈ 1.73.
A) v₁sinθ₁ = v₂sinθ₂
B) v₂sinθ₁ = v₁sinθ₂
C) sinθ₁ / v₁ = sinθ₂ / v₂
D) v₁v₂ = sinθ₁sinθ₂
Correct Answer: B
From Snell's Law, n₁sinθ₁ = n₂sinθ₂. We also know n₁ = c/v₁ and n₂ = c/v₂. Substituting these into Snell's Law gives: (c/v₁)sinθ₁ = (c/v₂)sinθ₂. The constant c cancels from both sides, leaving (1/v₁)sinθ₁ = (1/v₂)sinθ₂. Multiplying both sides by v₁v₂ gives v₂sinθ₁ = v₁sinθ₂.
A) n₁ > n₂ and v₁ < v₂
B) n₁ < n₂ and v₁ > v₂
C) n₁ > n₂ and v₁ > v₂
D) n₁ < n₂ and v₁ < v₂
Correct Answer: A
According to Snell's Law, n₁sinθ₁ = n₂sinθ₂. If θ₂ > θ₁, then sinθ₂ > sinθ₁, which implies that n₁ must be greater than n₂ to maintain the equality. Since the index of refraction is inversely proportional to speed (n = c/v), if n₁ > n₂, then the speed of light in medium 1 (v₁) must be less than the speed of light in medium 2 (v₂).
A) 0°
B) 45°
C) 90°
D) It depends on the indices of refraction.
Correct Answer: A
If the ray is directed along the normal, the angle of incidence (θ₁) is 0°. According to Snell's Law, n₁sin(0°) = n₂sinθ₂. Since sin(0°) = 0, the equation becomes 0 = n₂sinθ₂. For this to be true, sinθ₂ must be 0, which means the angle of refraction (θ₂) is also 0°. The ray passes through without changing direction.
A) sin(θc)
B) 1 / sin(θc)
C) cos(θc)
D) 1 / cos(θc)
Correct Answer: A
For total internal reflection from X to Y, n_X > n_Y. The critical angle formula is sin(θc) = n_Y / n_X. The index of refraction is n = c/v. Therefore, n_Y = c/v_Y and n_X = c/v_X. Substituting these into the critical angle formula gives sin(θc) = (c/v_Y) / (c/v_X). The 'c' terms cancel, leaving sin(θc) = v_X / v_Y.
A) Light traveling from Medium B to Medium A.
B) Light traveling from Medium A to Medium B.
C) When the angle of incidence is exactly 90 degrees.
D) When the angle of incidence is 0 degrees.
Correct Answer: B
Total internal reflection can only occur when light passes from a medium with a higher index of refraction to a medium with a lower index of refraction. In this case, n_B (2.0) > n_A (1.5). Therefore, TIR is possible when light travels from B to A, but it is impossible when light travels from A to B.