Physics (Essay) Paper 2 WASSCE (PC), 2016

Question 3

 

 

A wire of length 6.5 m and diameter 3.0 mm extends by 0.20 mm when a force of 60 N acts on it. Calculate the stress on the wire. [π – 3.14]

Observation

 

 

This is a popular question among candidates. Candidates stated the correct formula but could not evaluate the “Area” correctly. Also most candidates failed to consider conversion of units while others simply could not converts units successfully (from “mm” to “m” or vice versa). Performance was low.

The expected answer is: