Lesson: Thermal Expansion of Solids and Liquids Physics • 9th Grade

In this lesson, we will learn how to calculate the linear and volumetric expansion of solids and liquids due to their change in temperature.

Lesson Plan

Students will be able to

relate the change in temperature of a long, thin, solid object to the linear thermal expansion of the object using the equation , where is the coefficient of linear thermal expansion,
relate the change in temperature of a solid object to the volumetric thermal expansion of the object using the equation , where is the coefficient of volumetric thermal expansion,
describe qualitatively how interactions between particles in water affect the variation in density of water between a temperature of and .

Lesson Worksheet

Q1:

A solid rod is made of a substance that has a linear coefficient of thermal expansion of . The rod increases in length by 0.12 mm when its temperature increases by . Find the length of the rod after this temperature increase. Answer to three significant figures.

Q2:

Water in a tank is increased in temperature from to . The water volume increases by 0.25 L. Find the volume of the water before the temperature increase. Use a value of for the volume coefficient of expansion of water. Answer to three significant figures.

Q3:

Two wires increase in length by the same amount when both their temperatures increase by the same amount, as shown in the diagram. Before the temperature increase, the longer wire is 1.2525 m long. The shorter wire’s linear coefficient of thermal expansion is 1.135 times that of the longer wire. How much shorter is the shorter wire before the temperature increase? Answer to three significant figures.