Matlab Question: Given code how would you answer part below? syms x; % Constants

Question

Matlab Question: Given code how would you answer part below?

syms x;

% Constants
a=10;
b=7;
k=20;

% User input
w = input('Enter Weight: ');
xl = input('Enter bracket xl: ');
xu = input('Enter bracket xu: ');

% Calcuations
l0 = sqrt(a^2 + b^2);
l = sqrt(a^2 + (b+x)^2); % Length as a function of x
W = 2*k*(l-l0)*(b+x)/l; % Relating W value to x for the main equation

% Default initialization
xr_old = xl;
xr_new = xu;

% Iteration counter
iter=1;

fprintf(' Solution By: Name');
fprintf(' Date : Date');
fprintf(' W = %f lb',w);
fprintf(' Iteration Xl(in) Xu(in) Xr(in) error(%c)','%');
fprintf(' -------------------------------------------------------------------------------------');
while(1)
xr_new = (xl + xu)/2; % Bisecting the interval
  
err = abs((xr_new-xr_old)/xr_new); % Calculating error with respect to old root
  
fprintf(' %d %f %f %f %f',iter,xl,xu,xr_new,err*100);
  
if(err<0.005) % Checking relative error percentage
solution = xr_new;
break;
else
  
if(eval(subs(W,xr_new))*eval(subs(W,xl))<0) % Checking if bisection point has differen sign that the upper/lower brackets
xu = xr_new;
else
xl = xr_new;
end
xr_old = xr_new; % Assigning earlier calculated root to become old root
iter=iter+1; % Increasing iteration count
end
end
fprintf(' -------------------------------------------------------------------------------------');
fprintf(' Solution: x = %f (in) ',solution);

To verify the functionality of your program, test your program using the weight values listed in Table 1. To record the verification process, open a diary named A5TESTlastname.txt and close it after executing the five test cases. In each case, use an initial bracket estimate of x 0 and xu- 15 inches. Check your program with hand calculations that solve for the weight given the program output deflection (a) and compare the resulting values for the weight in each of the five test cases Table 1. Verification Results Case Weight Program Solution Hand Calculation Check No. W (Ib) (Ib) x (in) 10 20 50 100 2 4

Explanation / Answer

I think your given parameters or your code is not correct .

Irrespective of weights the program is outputting a result 7.50000 and error is 100%

As of it I can't make a correct answer.But,I have a method to solve this problem.

This solution has two steps:

First step is easy correct your code and run it with different weight values.

Second step:

->From your code a=10,b=7,k=20,xl=0,xu=15 these are constant in our scenario

->l0=sqrt(a^2 +b^2) which is a constant since a and b does'nt change

so, l0=12.20656(approx.)

-> l=sqrt(a^2 + (b+x)^2 ) which is Lenght function in term of x (this x is the value we obtained after the program is executed).

-> W= 2*k*(l-l0)*(b+x)/l

this is the weight which we should find using the x(solution) obtained earlier while executing

for example

if    w=5, x =7.5

then l=sqrt(a^2 + (b+x)^2 )

will be l=sqrt(a^2 + (b+7.5)^2 ) ,after substituting a =10 b=7

we get l=sqrt(10^2 +(14.5)^2) which is approximately 17.61395

Now we need to find W

W= 2*k*(l-l0)*(b+x)/l (in here we substitute l= 17.61395 b=7 k=20 x=7.5 l0=12.20656)

after substitution we get W=178.0569 lb

similarly we can find W for different w values.

Hope I helped!

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