Question

A force of 15 N will stretch a rubber band 10 cm ​(0.10 ​m). Assuming that​ Hooke's law​ applies, how far will an 18​-N force stretch the rubber​ band? How much work does it take to stretch the rubber band this​ far?

Answer 1

Answer: a) extension = 0.12m, b) work done = 2.16 J

Step-by-step explanation: according to hooke's law, provided that elastic limit is kept constant force (f) is proportional to extension (e).

F = ke, k = F / e.

F1/e1 = F2/e2

F1 = 15 N, e1 = 0.10m, F2= 18 N, e2 =?

15/0.10 = 18/e2

e2 = 18 * 0.10/ 15

e2 = 1.8/15

e2 = 0.12m.

Work done at this extension = F2 * e2

Work done = 18 * 0.12 = 2.16 J