Light travels through a glass block at 2.00 × 10^8 m/s. Use c = 3.00 × 10^8 m/s to calculate the refractive index.

Final answer: 1.50. Refractive index compares light's vacuum speed with its speed in the material, so use n = c/v. Substitute the two speeds: n = (3.00 × 10^8 m/s) / (2.00 × 10^8 m/s) = 1.50. The speed units cancel, so refractive index has no unit; n > 1 is consistent with light travelling more slowly in glass than in vacuum.

MYP Physics · 11 · free response

Speed of light in glass

Light and optics · Original GioPhysics question with a detailed, mark-by-mark answer guide.

Demand: routine
Marks: 4
Topics: 1
Answer: Complete

Question4 marks

Light travels through a glass block at 2.00 × 10⁸ m/s. Use c = 3.00 × 10⁸ m/s to calculate the refractive index.

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Develop a connected physics argument and support each claim with a relationship, calculation, or observation.

Name the standard relationship first, keep units attached, and show the substitution before the result.

Response type: free response
Allocation: 4 marks
Demand: routine

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