A spring with spring constant of 28 N/m is stretched 0.2 m from its equilibrium position.

How much work must be done to stretch it
an additional 0.06 m?
Answer in units of J

1 answer

F1 = (0.2m/1m) * 28N = 5.6 N. To stretch
spring 0.2 m.
Work = F1 * d = 5.6 * 0.2 - 1.12 J.

F2 = (0.2m+0.06m)/1m) * 28 N.=7.28 N.
Work = F2 * d = 7.28 * 0.26 = 1.89 J.

1.89-1.12 = 0.77 J. to stretch it an additional 0.06 m.