The coefficient of stiffness of a weightless spring is 50 N / m. How much does the 3 kg weight stretch the spring?

Initial data: k (coefficient of stiffness of a weightless spring) = 50 N / m, m (mass of the load that stretches the spring) = 3 kg.

Constants: g (acceleration due to gravity) = 10 m / s ^ 2.

The force of gravity from the action of the mass of the load will be balanced by the elastic force of the spring:

Ft = Fcont; m * g = k * ∆l and ∆l = m * g / k.

Let’s do the calculation:

∆l = 3 * 10/50 = 30/50 = 0.6 m or 60 cm.

Answer: A weight of 3 kg will stretch the weightless spring by 0.6 m (60 cm).