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

Question 5

 

 

(a)        Why are optical fibres wrapped in bundles?

    (b)        By what optical phenomenon does an optical fibre transmit light along its axis?    

 

Observation

 

Few candidates failed to realize that optical fibres are wrapped in bundles so as to transmit light in and out of a confined space. Also, candidates failed to recognize the fact that “Total Internal Reflection” as a phenomenon by which light is transmitted. Performance was below average.

 

 The expected answer is as stated below:

            (a)        Reason for wrapping optical fibres in bundles

                        To carry light into or out of a confined space

            (b)        Optical phenomenon by which optical fibre transmits light along its axis                               

                                    Total internal reflection