A wide range of springs for use in the science laboratory.
(Wikipedia excerpt: …..”..A spring (S) is an elastic object that stores mechanical energy. (S) are typically made of (S) steel. There are many (S) designs. In everyday use, the term often refers to coil (S) . When a conventional (S) , without stiffness variability features, is compressed or stretched from its resting position, it exerts an opposing force approximately proportional to its change in length (this approximation breaks down for larger deflections). The rate or spring constant of a spring is the change in the force it exerts, divided by the change in deflection of the spring.
That is, it is the gradient of the force versus deflection curve. An extension or compression (S) rate is expressed in units of force divided by distance, for example or N/m or lbf/in…A torsion (S) is a (S) that works by twisting; when it is twisted about its axis by an angle, it produces a torque proportional to the angle. A torsion (S) rate is in units of torque divided by angle, such as N·m/rad or ft·lbf/degree. The inverse of (S) rate is compliance, that is: if a (S) has a rate of 10 N/mm, it has a compliance of 0.1 mm/N. The stiffness (or rate) of (S) in parallel is additive, as is the compliance of springs in series...”)