Question

an elastic string stretched to a total Length of 30 under a load of 500N. with an additional load of 100N, the string stretches by a further 2cl the natural length of the string is unknown?

Answer 1

x = additional stretch length so F = kx so x = F/k
n = natural length
30 = n + 500/k
30+ 2cl = n + 600/k (I have no idea what 2 cl means)
------------------------------------ so
2cl = 100/k
solve for k and go back and get n as well