The spring constant

The spring constant, k, is a measure of the stiffness of the spring.

It is different for different springs and materials.

The larger the spring constant, the stiffer the spring and the more difficult it is to stretch.


A force of 3 N is applied to a spring. The spring is not stretched beyond the limit of proportionality and it stretches by 15 cm. Calculate the spring constant.

F = 3 N

e = 15 cm = 0.15 m

F = ke

k = \frac{\text{F}}{\text{e}}

k = 3 N ÷ 0.15 m

k = 20 N/m

The spring constant is 20 N/m.