# If the length of a 24 cm spring increases to 59 cm when a 5 kg weight is hanging from it, what is the spring's constant?

Dec 11, 2015

I found: $k = 1.96 \frac{N}{m}$

#### Explanation:

Consider the diagram:

Choosing the origin at the extreme of the un-extended spring:
at equilibrium:
${F}_{e l} - W = 0$
$- k y = m g$
$- k \left(- h\right) = m g$
$- k \left(- 25\right) = 5 \cdot 9.8$
$k = 1.96 \frac{N}{m}$