Question

The frequency of visible light of wavelength 6000 A.U. (Angstrom units) is
1. 4 x 10^14 Hz
2. 6000 Hz
3. 5 x 10^10 Hz
4. 5 x 10^14 Hz

Answer 1

Frequency = Speed/ wavelength

here visible light speed is 3× 10^8 m/s

wavelength = 6000AU
1AU = 1×10^-10 m

frequency =
3× 10^8/ 6000×10^-10

frequency = 5× 10^ 14 Hz

so Option 4 is correct.

Answer 2

Frequency = Speed/ wavelength
f = s x λ

Speed of light (vacuum) = 3 x 10⁸ m/s

Given wavelength = 6000 A.U


f = 3 x 10⁸/ 6000 x 10⁻¹⁰ (∵1A . U = 1 x 10⁻¹⁰ m)
f= 5 x 10¹⁴ Hz

Correct Option -- 4

Hope This Helps You!