When equal forces are applied to two springs with spring constants $1500 \, N/m$ and $3000 \, N/m$,what is the ratio of their stored potential energies?

$A$ spring with a force constant of $800 \ N/m$ is stretched by $5 \ cm$. Find the work done in stretching it from $5 \ cm$ to $15 \ cm$ in $J$.

$A$ spring with spring constant $k$ when stretched through $1 \, cm$,the potential energy is $U$. If it is stretched by $4 \, cm$,the potential energy will be (in $U$)

$A$ spring,when stretched by $2 \,mm$,has a potential energy of $4 \,J$. If it is stretched by $10 \,mm$,its potential energy will be:

To simulate car accidents,auto manufacturers study the collisions of moving cars with mounted springs of different spring constants. Consider a typical simulation with a car of mass $1000 \; kg$ moving with a speed $18.0 \; km/h$ on a smooth road and colliding with a horizontally mounted spring of spring constant $6.25 \times 10^{3} \; N m^{-1}$. What is the maximum compression of the spring in $m$?

Does the energy stored in a spring change when it is stretched or compressed?