Forces in action _______________________________________________________________________________________________________________________________________________________________________________________________________________________
6. Stretching a spring. Hooke´s law
Figure 9.3• Elasticity is the property of an object or material which causes it to be restored to its original shape after distortion.
• A spring is an example of an elastic object- when stretched, it exerts a restoring force which tends to bring it back to its original length.
• Hooke’s Law: the restoring force is generally proportional to the amount of stretch.
Hookes´s Law
The extension or compresion (deformation) of an elastic body is directly proportional to the force applied to it.
There is a negative sign on the right-hand side of the equation because the restoring force always acts in the opposite direction of the displacement (for example, when a spring is stretched to the left, it pulls back to the right).