forces and elasticity

• when a force causes an object to move work is done

  this is because it requires energy to move the object
• one joule = 1 newton metre
• to change the shape of an object more than one force must be applied
• if the forces are removed and it returns back to its original shape it was elastically deformed
• if the object does not return back to its original shape it has been inelastically deformed
• • the extention of an elastic object is directly proportional to the applied force
  • however once the limit of proportionality has been exceeded the relation ship is no longer linear , doubling the force will not double the extention and the graph will not be a straight line
• the spring constant indicated how easy it is to stretch or compress, the higher the spring constant the stiffer the spring