The work done in stretching a spring of natural length $25 \ cm$ and spring constant $50 \ Nm^{-1}$ from $50 \ cm$ to $60 \ cm$ is (in $J$)

$A$ spring of original length $L$ and spring constant $K$ is stretched by a small length $x$. It is further stretched by another small length $y$. Find the work done in the second stretching.

The work done in joules in increasing the extension of a spring of stiffness $10\, N/cm$ from $4\, cm$ to $6\, cm$ is:

$A$ spring with a spring constant of $5 \times 10^3 \ N/m$ is initially in its natural state. It is stretched by $5 \ cm$. How much work is required to stretch it by another $5 \ cm$?

If a spring extends by $x$ on loading,then the energy stored in the spring is (where $T$ is the tension in the spring and $K$ is the spring constant):

$A$ long spring, when stretched by a distance $x$, has the potential energy $u$. On increasing the stretching to $nx$, the potential energy of the spring will be: