Drag force calculations

In fluid mechanics the drag force exerted by the surrounding medium( fluid) plays an important role in motion study. The drag force is calculated by the formula,

dragforce=0.5*(density of fluid)*(frontal area)*(velocity)^2*(drag coefficient)

1. Drag force vs velocity

function [dragforce]=myf(a,v,rho,cd)
dragforce=0.5*a*rho*v.*v.*cd;

plot(dragforce,v,\'linewidth\',3)
xlabel(\'drag force\')
ylabel(\'velocity\')
grid on

end

On entering values of frontal area, velocity and density of air ; the function returns the drag force value and also the plot for various values of drag force for different values of velocity is plotted. In case if there are different values of velocity forming an array, element wise operator \".\" is used. Inputs given to the function are included in the output screenshot.

2.Drag force vs drag coefficient

Similarly a graph for drag force vs drag coefficient can also be made. Here the values of drag coefficient are varied , unlike previous example where velocity values were varied.

function [dforce]=func(a,v,rho,cd)

dforce=0.5*cd.*v.*v.*a*rho;

plot(dforce,cd,\'linewidth\',3)
xlabel(\'draq force\')
ylabel(\'drag coefficient\')
end

The inputs are covered in the output screenshot.