a$)$ Explain the term $$Scientific method$$ and how this affects testing and measurement strategy in Tensile Tests. Describe an outline of testing procedures based on:

$$ Formulate a question.

$$ Hypothesis

$$ Prediction

$$ Testing

$$ Analysis

In a tensile test on a polycarbonate strip, the following observations applied:

The initial length, width and thickness of the strip was measured and then the strip was put into the tensile machine. The strip was observed to increase in its length proportionally to the applied force during the elastic phase of the experiment. Following the elastic phase, elongation was observed in the strip without any additional force. Thereafter the strip continued to increase in length when the force was decreased. This phase continued for a long while till the strip got destroyed in a fracture.

The following data outlines the readings obtained before and after the experiment.

Material for test specimen: Polycarbonate strip

Dimensions before test:

Length $75$ mm$,$ Width $10$ mm$,$ Thickness $4$ mm$.$

Dimensions after test:

Length $126\mathrm{.}6$ mm$,$ Width: $8\mathrm{.}3$ mm$,$ Thickness: $3\mathrm{.}2$ mm