Objective 02: The Theory of Thermal Expansion and Linear Expansion

Question 1

Theory of Thermal Expansion

Answer 1

Heat is transformed into internal energy (kinetic energy plus potential energy) by each molecule of the material. As the molecules gain energy and vibrate more rapidly, the average space between the molecules increases. The result is a change in the overall dimensions of the material.

Question 2

How does a long, thin material respond to heat transfer?

Answer 2

It will expand mainly in length

Question 3

How does a flat material with relatively large surface area respond to heat transfer?

Answer 3

It will expand mainly in length and width, i.e. area.

Question 4

What are the 3 main factors that determine the extent to which the dimensions of an object will change when it is heated?

Answer 4

1. The material from which the object is made
2. The original dimensions of the object before heating
3. The temperature change magnitude

Question 5

Is the coefficient of linear expansion constant for a material, regardless of temperature, and if not, what value is used?

Answer 5

No, an average is used