Question

differentiate between linear and cubical expansion

Answer 1

Linear expansion means change in one dimension (length) as opposed to change in volume (volumetric expansion). To a first approximation, the change in length measurements of an object due to thermal expansion is related to temperature change by a "linear expansion coefficient". It is the fractional change in length per degree of temperature change. Assuming negligible effect of pressure, we may write:

where is a particular length measurement and is the rate of change of that linear dimension per unit change in temperature.

The change in the linear dimension can be estimated to be:

This equation works well as long as the linear-expansion coefficient does not change much over the change in temperature , and the fractional change in length is small . If either of these conditions does not hold, the equation must be integrated.

Area expansion

The area thermal expansion coefficient relates the change in a material's area dimensions to a change in temperature. It is the fractional change in area per degree of temperature change. Ignoring pressure, we may write:

where is some area of interest on the object, and is the rate of change of that area per unit change in temperature.

The change in the area can be estimated as:

This equation works well as long as the area expansion coefficient does not change much over the change in temperature , and the fractional change in area is small . If either of these conditions does not hold, the equation must be integrated.

Answer 2

Answer:

Linear expansion means change in one dimension (length) as opposed to change in volume (volumetric expansion). ... The area thermal expansion coefficient relates the change in a material's area dimensions to a change in temperature. It is the fractional change in area per degree of temperature change.

Explanation:

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