A spring has a length of 0.260 m when a 0.300 kg mass hangs from it, and a length of 0.750 m when a 1.90 kg mass hangs from it.(a) What is the force constant of the spring?(b) What is the unloaded length of the spring?

1 answer

m1*g = 0.30kg * 9.8N/kg = 2.94 N.
L1 = 0.26 m.

m2*g = 1.90kg * 9.8N/kg = 18.62 N.
L2 = 0.75 m.

a. K = (N2-N1)/(L2-L1)
K = (18.62-2.94)/(0.75-0.26) = 32 N/M

b. (2.94N/32N) * 1M = 0.092 M.

L + 0.092 = 0.26
L = 0.26 - 0.092 = 0.168 M.