Question

Assume that 10 ft-lb of work is required to stretch a spring 1 ft beyond its natural length. What is the spring constant?

Answer 1

$W=\int^b_a kxdx=k\int^b_axdx=k(x^2/2)|^b_a =k(b^2/2-a^2/2)$

W=10

a=0

b=1

$10=k(1/2-0)=k/2$

k=20