After stretching the spring 4 cm, work of 2 J is done. Find the work if the spring is stretched 8 cm.

Answer 1

First, find the spring constant k, then use it to find the work.

k = 2W₁ / x₁² = 2(2 J) / (0.04 m)² = 2500 N/m

W₂ = kx₂² / 2 = (2500 N/m)(0.08 m)² / 2 = 8 J