find the work done in stretching the spring from its natural length to a length of 0.5 meters.

Question

If the natural length of a spring is 0.4 meter, and if its takes a force of 14 newtons to keep it extended an additional 0.05 meters,find the work done in stretching the spring from its natural length to a length of 0.5 meters. 

______Joules

Answer 1

F = k·Δx; k = F/Δx = 14N/0.05m = 280 N/m

W = k(x₁ - x₀)²/2 = 280N/m·(0.5m - 0.4m)²/2 = 1.4 J