In: Advanced Math
Q 3. The total mass of a variable density rod is given by
m=
where m = mass, ρx= density, Ac(x) = cross-sectional area, x = distance along the rod, and
L = the total length of the rod. The following data have been measured for a 20m length rod.
Determine the mass in grams to the best possible accuracy.
x,m |
0 |
2 |
4 |
6 |
8 |
10 |
12 |
14 |
16 |
18 |
20 |
|
ρ, g/cm2 |
4.00 |
3.98 |
3.95 |
3.89 |
3.80 |
3.74 |
3.6 |
3.55 |
3.41 |
3.37 |
3.30 |
|
Ac, cm2 |
100 |
102 |
103 |
106 |
110 |
114 |
120 |
130 |
133 |
1142 |
150 |
|
Q 4.With the aid of fourth order Runge-Kutta method, solve the competing species model
defined by
where the populations and are measured in thousands and t in years. Use a step size of
0.2 for 0 ≤ t ≤ 2 and plot the trajectories of the populations with Matlab or GNU Octave.