Question

It is determined that a certain wave of infrared light has a wavelength of 8.45 mm. Given that c=2.99 ×108 m/s, what is the frequency of this infrared wave? (Round your answer to three significant figures.) Hz

Answer 1

Answer:

f=3.54 × 1010 Hz

Explanation:

Use the relationship  f=vλ  to solve for frequency f. Substituting the known quantities yields:

 

λ=8.45  mm = 8.45 ×10-3 mf=vλf=2.99 × 108 m/s8.45 ×10-3  mf=3.538×1010  

 

answer rounded off to 3 significant digits is

 

f=3.54 × 1010 Hz

Answer 2

Answer:

The frequency of infrared wave is 35.385 GHz

Explanation:

Given data:

Wavelength of infrared light = 8.45 mm = 8.45 x $10^{-3}$ m

Velocity of infrared light = 2.99 x $10^{8}$ m/s

To find: frequency of the infrared wave = ?

We know that the wavelength and frequency are inversely proportional and the formula to derive frequency with velocity and wavelength is:

c = μλ, where

c is velocity of light

μ is frequency of light

λ is wavelength of light

Hence the frequency of light  μ = c/λ

                                                     = $\frac{2.99 x 10^{8} m/s }{8.45 x 10^{-3}m }$

                                                     = $\frac{299}{8.45}$ x $10^{9}$ $s^{-1}$

                                                     =  35.385  x  $10^{9}$ Hz   (since 1 $s^{-1}$ = 1 Hz)

                                                     = 35.385 GHz