Answer:
The extension of the spring is 0.392 m.
Step-by-step explanation:
Given;
spring constant, k = 50 N/m
mass attached to the spring, m = 2.0 kg
let the extension of the spring = x
The extension of the spring is calculated by applying Hook's law;
F = kx
mg = kx

Therefore, the extension of the spring is 0.392 m.