Question

A force of 100 Newtons will stretch a spring 0.25 meter. How far will a force of 80 Newtons stretch it?
A. 2 m
B. 0.2 m
C. 0.04 m
D. 0.4 m

Answer 1

It's a straightforward proportion, because Hooke's Law is \(F=kx\), when the deformations are small enough. You've got values for \(F\) and \(x\) which you can use to find \(k\) to apply to your second value of \(x\).

Answer 2

Or, observing that the force/deformation is linear, multiply the ratio of the deformations with the known force to get the other force.

Answer 3

Sorry, ratio of the forces with the known deformation...