# If a spring has a constant of 4 (kg)/s^2, how much work will it take to extend the spring by 63 cm ?

Feb 16, 2017

I got $0.8 J$
We will need to do work $W$ to extend the spring that, as a result, will acquire an Elastic Potential Energy equal to $\frac{1}{2} k {x}^{2}$:
$W = \frac{1}{2} k {x}^{2}$
$W = \frac{1}{2} \cdot 4 \cdot {\left(0.63\right)}^{2} = 0.7939 \approx 0.8 J$