REQUIRED PRACTICAL 4
Step 1 - (correct Answer) - 1. find cross sectional area (πr²) of the wire, using micrometre, find diameter
at different 90° along the wire - find the average diameter.
before you start - (correct Answer) - do a pilot experiment to find the limit of proportionality, you won't
pass it in the experiment.
Step 2 - (correct Answer) - clamp the wire to the bench, then position it on the pulley
Step 3 - (correct Answer) - measure starting position of the wire with a millimetre ruler and marking it
on the wire.
Step 4 - (correct Answer) - measure the distance between the the fixed end of the wire and the marker =
unstretched length
Step 5 - (correct Answer) - increase the weight in intervals e.g 100g, measure extension each time
Step 6 - (correct Answer) - use results to plot a stress, F/A - strain, ∆L/L graph
Step 1 - (correct Answer) - 1. find cross sectional area (πr²) of the wire, using micrometre, find diameter
at different 90° along the wire - find the average diameter.
before you start - (correct Answer) - do a pilot experiment to find the limit of proportionality, you won't
pass it in the experiment.
Step 2 - (correct Answer) - clamp the wire to the bench, then position it on the pulley
Step 3 - (correct Answer) - measure starting position of the wire with a millimetre ruler and marking it
on the wire.
Step 4 - (correct Answer) - measure the distance between the the fixed end of the wire and the marker =
unstretched length
Step 5 - (correct Answer) - increase the weight in intervals e.g 100g, measure extension each time
Step 6 - (correct Answer) - use results to plot a stress, F/A - strain, ∆L/L graph
