This is a minimisation problem where I get input from the user for W, lb and lc. And find the minimum value of T for minimum of D. T is given by the relationship as seen in the program. I keep on getting error on that. Thanks for any help.

L c

D

W

L b

Problem: A cable of length L c supports a beam of length L b so that it is horizontal when 

the weight W is attached to the beam end. The tension force T in the cable is given by the 

following equation: 
T 

L bL c W 
D L 2D 2 
c 

Where D is the distance of the cable attachment point to the beam pivot. 

Create an M-file that: 

a) Prompts for and accepts the following inputs from the Command Window : W, L b, and 

L c (the weight is in Newtons, and the lengths are in meters), then uses these values to 

compute and display in the Command Window the value of D that minimizes the 

tension, T , (do not use a loop in your M-file to perform this computation). 

b) Your M-file should also display the minimum tension value in the Command Window, 

and produce a well annotated graph of T versus D. 

c) Lastly, explain in a comment section at the bottom of your M-file how much the value 

of D can vary from it’s optimal value before the tension increases by more than 10% 

from it’s minimum.

Answer 1

[Alan Weiss]

This sounds like a transcription of a homework problem. We generally don't like to simply solve people's homework for them.

If you want help, show people what you have done, and where your program throws an error.

Alan Weiss

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