Hi,
Note how to use conditional operators [if... elseif.. else..end] within [for ... end] loop. The equations you have taken are corrected w.r.t nasa.gov info. T used in formulation of the speed of sound has to be absolute tempreature and thus: T = temp + 273.1
Here is the complete answer code:
h=linspace(0,100000);
temp=zeros(size(h)); % Memory allocation
pressure=zeros(size(h)); % Memory allocation
for ii = 1:numel(h)
if h(ii)<11000
temp(ii)=15.04-0.00649*h(ii);
pressure(ii)=101.29*((temp(ii)+273.1)/288.08)^5.256;
elseif h(ii)>11000 && h(ii)<25000
temp(ii)=-56.46;
pressure(ii)=22.65.*exp(1.73-0.000157*h(ii));
else
temp(ii)=-131.21+0.00299*h(ii);
pressure(ii)=2.488*((temp(ii)+273.1)/216.6)^(-11.388);
end
end
dens=pressure./(0.2869*(temp+273.1));
T = temp+273.1;
speedofsound = sqrt(1.4*286*T);
figure(1);plot(h,temp, 'r-*'); grid on, title('temp')
figure(2);plot(h,dens, 'b-o'); grid on, title('dens')
figure(3);plot(h, speedofsound, 'g-.x'); grid on, title('speed of sound')
