drag force calculation

% calculation of drag force

%inputs

% coefficient of drag

cd=0.1;

%density in kg/m^3

rho=1.2;

% frontal area in m^2

a=5;

%velocity of cycle in m/s

v=20;

% fd is drag force

%formula

fd=0.5*rho*a*v^2*cd;

plot(fd,v,\'line width\',2,\'color\',\'r\')

xlabel(\'drag force\')

ylabel(\'velocity\')

% calculation of drag force

%inputs

% coefficient of drag

cd=0.1;

%density in kg/m^3

rho=1.2;

% frontal area in m^2

a=[1:5];

%velocity of cycle in m/s

v=20;

% fd is drag force

%formula

fd=0.5*rho*a.*v^2*cd;

plot(fd,cd,\'linewidth\',3,\'color\',\'g\')

xlabel(\'drag force\')

ylabel(\'coefficient of drag\')

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You need to find the dragforce for a range of velocities

but you have found it only for 1 particular velocty