plotting y-axis issue and wrong plot

hi i'm writing a code for newton's 2nd law were very the mass

the first plot is Mass VS Acc

2ND Force VS Acc

3RD Force VS Mass

but i'm thinking i'm doing something wrong especially in the last plot because it look like the first one+ my axies are a bit wrong too so can anyone explain

clear 
clc
subplot(3,1,1)
hold on

for m=0:100:1000
    a=linspace(20,220,1000);
    f=m.*a;
    plot(f)
    title('mass V/s Acceleration');
xlabel('acceleration'); 
ylabel('mass')
end
legend m=0 m=100 m=200 m=300 m=400 m=500 m=600 m=700 m=800 m=900 m=1000
subplot(3,1,2)
hold on
for m=0:100:1000
   a=linspace(20,220,1000);
  
    f=m.*a;
    plot(a,f)
    title('Force V/s acceleration');
xlabel('acceleration'); 
ylabel('Force')
end
legend m=0 m=100 m=200 m=300 m=400 m=500 m=600 m=700 m=800 m=900 m=1000

subplot(3,1,3)
hold on
for m=linspace(0,1000,11)
    a=linspace(20,220,1000);
    M=linspace(0,1000,1000);
    f=m.*a;
    plot(M,f)
    title('Force V/s Mass');
xlabel('mass'); 
ylabel('Force')
end
legend m=0 m=100 m=200 m=300 m=400 m=500 m=600 m=700 m=800 m=900 m=1000

Answer 1

[VBBV]

subplot(3,1,3)
hold on
for m=linspace(0,1000,11)
  a=linspace(20,220,1000);
  M=linspace(0,1000,1000);
  f=M.*a;. % use M 
  plot(M,f)
  title('Force V/s Mass');
xlabel('mass'); 
ylabel('Force')
end

If you use M instead of m you can notice the difference.

Answer 2

[azarang asadi]

your m is 0:100:1000 which is a 1*11 but your a is 1*1000. It should be same size.

so m = 1:1000