The spring is compressed by 3 cm if a weight of 450 g is placed on it. Calculate the spring stiffness.

Data: Δx (deformation of the taken spring) = 3 cm = 0.03 m; m (mass of the weight placed on the spring) = 450 g = 0.45 kg.

Constants: g (acceleration due to gravity) ≈ 10 m / s2.

To determine the required spring stiffness, we will use the equality: Fcont = Ft and k * Δx = m * g, whence k = m * g / Δx.

Calculation: k = 0.45 * 10 / 0.03 = 150 N / m.

Answer: The spring rate is 150 N / m.