Question

A rubber band has a spring constant of 45N\m. If the rubber band is pulled by a force of 9.8N, (a) how far would it stretch?(b)what is the worked done by this force in stretching this string

Answer 1

(a)

$$F=kx,$$ $$x=\dfrac{F}{k}=\dfrac{9.8\ N}{45\ \dfrac{N}{m}}=0.218\ m.$$

(b)

$$W=\dfrac{1}{2}kx^2=\dfrac{1}{2}\times45\ \dfrac{N}{m}\times(0.218\ m)^2=1.07\ J.$$