I’m not suggesting anything of the sort, I feel I may have posted this in the wrong place given my predicament. And I do appreciate the help and time you have given me, thank you.
I am unsure are you able to provide any assistance on this. The force will likely involve the tension in the string and be a function of the angle at which the string makes with the horizontal.
The first part is simply a case of invoking the formula for normal mode frequencies and plugging in integers 1,2,3 giving.
V_1=(1/2L)*(TL/M)^(1/2) and V_2=(1/L)*(TL/M)^(1/2) hence nv_1 (n=1,2,3) second part I assume is a case of dividing the string up into parts as per the attached photo but...