%PROGRAM TO FIND OUT ELECTRIC FIELD INTENSITY AT POINT 'P'
%IN CARTESIAN COORDINATE SYSTEM
%FOR A POINT CHARGE

clear all;
clc;
epsilon_0 = input('Enter the value of free space permittivity = ');

P = input('Enter the position of point P in cartesian coordinate system = ');

Px = P(1);
Py = P(2);
Pz = P(3);

Q = input('Enter the position of point Q in cartesian coordinate system = ');

Qx = Q(1);
Qy = Q(2);
Qz = Q(3);

q = input('Enter the value of point charge in coulombs = ');

Rqpx = Px - Qx;
Rqpy = Py - Qy;
Rqpz = Pz - Qz;

%Calculate vector distance between point P and Q

Rqp = [Rqpx Rqpy Rqpz];

%Calculate scalar distance between point P and Q

R = sqrt((Rqpx^2)+(Rqpy^2)+(Rqpz^2));

%Calculate Components of Electric Field Vector

Ex = (q/(4*pi*epsilon_0*(R^3)))*Rqpx;

Ey = (q/(4*pi*epsilon_0*(R^3)))*Rqpy;

Ez = (q/(4*pi*epsilon_0*(R^3)))*Rqpz;

UnitVector_X_direction ='ax';

UnitVector_Y_direction ='ay';

UnitVector_Z_direction ='az';

disp('Electric Field Intensity due to Point Charge = ');

E = [Ex Ey Ez]