Question

The following table gives the approximate values of the coefficient of static friction μ, for various materials

Option/ Materials/ μ
1 /Metal on metal/ 0.2
2 /Wood on wood /0.35
3/ Metal on wood /0.4
4/ Rubber on concrete/ 0.7

To start moving a weight W, on a horizontal surface, you must push with a force F, where F=μW.
Write an m-file that achieves the following:
1. Uses fprintf to print out the option and material information to the command window
2. Prompt the user to input a value of W and the type of materials/option
 Check if the input values are valid (e.g. negative weights or non-integer/incorrect option numbers). Your
program should continue prompting the user to enter values until they are valid.

3. Use a switch statement to compute the force required. Use fprintf to print a statement including the materials
used and the force required.
Hint: You may want to use a while loop to ensure that the user enters valid inputs.

Answer 1

clc,clear

s=0;

f=0;

fprintf("The data table is\n");

fprintf('Option \t Materials \t Coeff.\n');

fprintf(' 1 \t Metal_on_metal \t 0.2\n');

fprintf(' 2 \t Wood_on_wood \t 0.35\n');

fprintf(' 3 \t Metal_on_wood \t 0.4\n');

fprintf(' 4 \t Rubber_on_concrete \t 0.7\n');

prompt = 'Enter the weight of material ';

z = 0;

while z<=0 || ~(isinteger(z))

            z= input(prompt);

end

s=input('Enter your option');

while s ~= '1,2,3,4';

            s = input('Chooose your option from (1,2,3,4) ', 's');

end

switch s

    case 1

           f=0.2*z;

           fprintf('%f',f);

    case 2

           f=0.35*z;

           fprintf('%f',f);

    case 3

           f=0.4*z;

           fprintf('%f',f);

   case 4

           f=0.7*z;

           fprintf('%f',f);

   otherwise

           printf("Sorry");

end