Q. The frequency of a light wave in a material is 2 × 10¹⁴ Hz and wavelength is 5000 Å. The refractive index of material will be
A) 1.50
B) 3.00
C) 1.33
D) 1.40
Explanation
[Solution from source] Speed in the material v = fλ = 2 × 10¹⁴ × 5 × 10⁻⁷ = 1 × 10⁸ m/s, so n = c/v = 3 × 10⁸/1 × 10⁸ = 3.00. 1.50 comes from a slip in the power of ten. Answer (2).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.