Physics (Essay) Paper 2 WASSCE (PC), 2020

Question 4

 

 

The diagram above is graph of load against extension for a wire under varying tension. Identify the:

  1. Segment in which Hooke’s law is obeyed;
  2. Segment where elasticity holds;
  3. Yield point.

 

Observation

 

Most candidates failed to recognize the unlabeled origin of a given graph as a necessary starting point for parts (a) and (b). for instance, the origin to point A for segment (a) and origin to point B for segment (b)

The expected answers

-       (a)    Segment in which Hooke’s law is obeyed

                          The straight line                                                                                 

(b)           Segment where elasticity holds

                      The straight line plus AB                                                                  

         (c)             Yield point

                                    C