Question

Calculate the bandwidth of the light for the following wavelength ranges(assume a propagation speed of 2* 108). a.1000 to 1200nm b.1000 to 1400nm

Answer 1

We can use the formula f = c / λto find the corresponding frequency for each wave

length as shown below (c is the speed of propagation):

 a. B = [(2 ×108)/1000×10−9] −[(2 ×108)/ 1200 ×10−9] = 33 THz

 b. B = [(2 ×108)/1000×10−9] −[(2 ×108)/ 1400 ×10−9] = 57 THz

thank u

 

Answer 2

Communications and networking

Given:

Propagation speed is $2\times10^{8} \ m/s.$

Wavelength Range is 1000 to 1200 nm and 1000 to 1400 nm.

To find:

Bandwidth of light in respective range.

Steps:

We know that frequency can be written as

$f=\frac{c}{\lambda}$

where f is frequency,

c is propagation speed,

λ is wavelength.

So ,

(a) wavelength range is 1000nm to 1200 nm

as propagation speed is in m so we will convert this range in m,

hence range will be $1000\times 10^{-9} \ m \ to\ 1200\times 10^{-9}\ m$

Bandwidth of light will be

$[\frac{2\times 10^8}{1000\times 10^{-9}}] -[\frac{2\times 10^8}{1200\times 10^{-9}} ]\\\\\implies 3.3\times 10^{13}$

or it can be written in 33 THz as we know that 1 tetra hertz is $10^{12}$ hertz.

(b) wavelength range is 1000nm to 1200 nm

as propagation speed is in m so we will convert this range in m,

hence range will be $1000\times 10^{-9} \ m \ to\ 1400\times 10^{-9}\ m$

Bandwidth of light will be

$[\frac{2\times 10^8}{1000\times 10^{-9}}] -[\frac{2\times 10^8}{1400\times 10^{-9}} ]\\\\\implies 5.7\times 10^{13}$

or it can be written in 57 THz as we know that 1 tetra hertz is $10^{12}$ hertz.