springs

• deformation

  changing the shape of an object permanently
• for an object to become deformed, pair of equal AND opposite forces must be applied to it
• elastic deformation

  once distorting force is removed, object will return to original shape
• plastic deformations

  once distorting force has been removed from an object, doesn't return to its original shape
• tensile forces

  equal and opposite forces causing extension in an object
• compressive forces

  equal and opposite forces causing compression of an object
• investigation to stretch a wire

  • set up apparatus
  • plot extension against tension with extension on the x axis
  • before the wire snaps, begin removing masses and continue to plot extensions.
  • summarise findings
• elastic extension force is proportional to extension

  F$\infty$X

  This is only for elastic deformation
• F=KX

  K being the spring constant(force)