# Nature of Lights | Optics C++

These post series aim to solve examples and problems from Introduction to Optics book which is writen by Frank L. Pedrotti, Leno M. Pedrotti and Leno S. Pedrotti.

## Chapter 1: Nature of Lights

### Example 1

An electron is accelerated to a kinetic energy Ek of 2.5 MeV. (a) Determine its relativistic momentum, de Broglie wavelength, and speed. (b) Determine the same properties for a photon having the same total energy as the electron.

### Example 2

A certain sensitive radar receiver detects an electromagnetic signal of frequency 100 MHz and power (energy/time) 6.63 x 10^-16 J/s
a. What is the wavelength of a photon with this frequency?
b. What is the energy of a photon in this signal? Express this energy in J and in eV.
c. How many photons/s would arrive at the receiver in this signal?
d. What is the energy (in J and in eV) of a visible photon of wavelength 555 nm?
e. How many visible (wavelength 555 nm) photons/s would correspond to a detected power of 6.63 x 10^-16 J/s
f. What is the energy (in J and in eV) of an X-ray of wavelength 0.1 nm?
g. How many X-ray photons/s would correspond to a detected power of 6.63 x 10^-16 J/s

### Example 3

Consider a 5 milliwatt Helium-Neon laser emitting a “pencil-like” beam with a divergence angle a of 1.3 milliradians. The laser cavity is designed so that the beam emerges from a surface area 2.5*10^-3 cm^2 at the output mirror.
a. Determine the solid angle in terms of R and a
b. Determine the radiance of this laser light source in units of W/cm2*sr.

### Problems

1-6 , 9-10, 12-17 Problems   #### Solution:

##### Output:

Today quote: “Easy-to-read things are hard to write” – Stephen King