The frequency of light ray having the wavelength 3000 A is - Vidyadip

MCQ

The frequency of light ray having the wavelength $3000 \mathring A$ is

A
(a) $9 \times 10^{-}$cycles $/ sec$
✓
(b) 10 cycles/sec
C
(c) $90 cycles / sec$
D
(d) $3000 cycles / sec$

✓

Answer

Correct option: B.

(b) 10 cycles/sec

(b) $\quad v=\frac{c}{\lambda}=\frac{3 \times 10^8}{3000 \times 10^{-10}}=10^{15}$ cycles $/$ sec

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