**A spring has a length of 0.200 m when a 0.300-kg mass hangs from it, and a length of 0.750 m when a 1.95-kg mass hangs from it. (a) What is the force constant of the spring? (b) What is the unloaded length of the spring? I found the spring constant which is 29.4 N/m, but I don’t get b.**

**Answer:**

let uloaded length be x.

then (0.2 - x)*k=0.3*g and (0.75-x)*k=1.95*g ( k= spring const. g= gravity)

dividing them u get x=0.100 m

ask for doubts