Final answer:
The thermal strain coefficient, often referred to in terms of the coefficient of linear expansion (alpha) or the coefficient of volume expansion (beta), is a measure of an object's dimensional response to temperature change. The coefficient of volume expansion is roughly three times the coefficient of linear expansion, denoted as β ≈ 3α.
Step-by-step explanation:
The question asks about what the thermal strain coefficient is represented by. In the context of thermal stress and expansion, the thermal strain coefficient is related to the coefficient of thermal expansion, represented by the Greek letter alpha (α). The coefficient of linear expansion (α) describes how the size of an object changes with a change in temperature. If the thermal strain coefficient refers to volume, it is often denoted by the coefficient of volume expansion, which is represented by the Greek letter beta (β). The coefficient of volume expansion is typically estimated to be approximately three times the coefficient of linear expansion (α), and this relationship can be noted as β ≈ 3α. Thermal stress occurs when the expansion or contraction due to temperature change is constrained, generating internal forces within the material.