A light string has its ends tied to two walls separated by a distance equal to five-eighths the length of the string. A 53 kg mass is suspended from the center of the string, applying a tension in the string.

What is the tension in the two strings of length L/2 tied to the wall? The acceleration of gravity is 9.8 m/s^2.
Answer in units of N.

2 answers

Draw the triangles.

half the weight is supported by each side.

Let theta be the angle from the wall horizontal to the string. Then on each side, SinTheta=Weight/(2*tension)

But tan cosTheta= half wall distance/halfstring distance
costheta= 5/8

But sin^2theta+cos^2theta=1
or weight^2/4Tension^2+25/64=1
solve for tension.
on a calculator it should look like:
nSolve((53*9.8/2*x)^2+(5/8)^2=1,x)

*=multiply