Step 1: First take a point from straight line part of the graph.
C.S.A= πR²
Strain= Load/C.S.A
Step 2: Calculate Strain
Stain= Extension/Original Length
Step 3: Youngs Modulus
Youngs Modulas= Stress/Strain
Tensile Strength
Take point from heightest point on graph.
Read load value.
Convert load to stress.
C.S.A= πR²
Max Stress= Max load/C.S.A
% Proof Stress
Step 1: Calculate % of original length. 0.1 or 0.2/100 * 60= 0.06 or 0.12
Step 2: Plot this value on extension axis. Step 3: Draw line parallel to straight line part of graph. Step 4: Read load value. This is proof load. Step 5: Convert proof load to proof stress Stress= Load/C.S.A
Tensile Strength= Max load/C.S.A = 412kn/78.55mm²= 1.808kn/mm²
% Proof Stress
0.1 or 0.2/100 * 60= 0.06 or 0.12 Plot this value on extension axis. Draw line parallel to straight line part of graph. Read load value. This is proof load. Max Stress= Max load/C.S.A = 94/78.55= 1.2kn/mm²