A piece of wire is stretched from Length l1 to a length of l2 (Step A) and then from length l2 to length l3 (Step B)

a] Write down an expression for the engineering strain associated with Step A.

b] Write down an expression for the engineering strain associated with step B.

c] Write down an expression for the true strain associated with step A.

d] Write down an expression for the true strain associated with step B.

e] Use the definition of engineering strain to write down an expression for the engineering strain associated with stretching the wire from length l1 to length l3, and compare this with the result of adding your answers to a and b.

f] Use the definition of true strain to write down an expression for the true strain associated with stretching the wire length l1 to length l3, and comapre this with the result of adding your answers to c and d

g] What can you deduce your asnwers to e and f?