Explanation of tensile stress and Young’s modulus were poorly stated by majority of the candidates.  While many scored for valid additional information, many others failed to relate tensile stress with a wire or rod.

The expected answers are:

(a) Tensile stress is the ratio of force  to  cross-sectional area of a wire/rod                                                                           
            It is expressed in Newton per metre squared (Nm-2) 
                       
(b) Young’s modulus is the ratio of tensile stress to tensile strain. It is expressed in Newton per metre squared. (Nm-2)