Q. The frequency of light ray having the wavelength $3000\mathring{\mathrm{A}}$ is
A) $9 \times 10^{13}cycles/s$
B) $10^{15}cycles/s$
C) $90\ cycles/s$
D) $3000\ cycles/s$
Explanation
(b) $v = \frac{c}{\lambda} = \frac{3 \times 10^{8}}{3000 \times 10^{- 10}} = 10^{15}cycle/s$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.