Physics (Essay) Paper 2 WASSCE (SC), 2017

Question 7

 

  1. List three advantages of p-n junction diode over diode valve

 

Observation

 

This question was not popular amongst students. This means that candidates were not adequately exposed to its topics. However, candidates were more comfortable with it than with question 6. Low performance was recorded to show vague knowledge.

The expected answer is

p – n junction diode                                                                                
-  needs low voltage to operate
-  does not need time to warm up
-  is not bulky

 -  is cheaper to manufacture (in large quantities)