 Lecture in Heat

(Last Updated On: December 8, 2017)

Lesson Objectives – the students should be able to:

• Convert from joules to calories and kilocalories and vice versa.
• Distinguish between the concepts of temperature and heat.
• Explain what is meant by specific heat, latent heat of fusion, and latent heat of vaporization.
• Apply the law of conservation of energy to problems involving calorimetry.
• Distinguish the three ways that heat transfer occurs: conduction, convection, and radiation.
• Solve problems involving the rate of heat transfer by convection and radiation.

Summary of Chapter 14

• Internal energy U refers to the total energy of all molecules in an object. For an ideal monatomic gas,
• Heat is the transfer of energy from one object to another due to a temperature difference. Heat can be measured in joules or in calories.
• Specific heat of a substance is the energy required to change the temperature of a fixed amount of matter by 1° C.
• In an isolated system, heat gained by one part of the system must be lost by another.
• Calorimetry measures heat exchange quantitatively.
• Phase changes require energy even though the temperature does not change.
• Heat of fusion: amount of energy required to melt 1 kg of material.
• Heat of vaporization: amount of energy required to change 1 kg of material from liquid to vapor.
• Heat transfer takes place by conduction, convection, and radiation.
• In conduction, energy is transferred through the collisions of molecules in the substance.
• In convection, bulk quantities of the substance flow to areas of different temperature.
• Radiation is the transfer of energy by electromagnetic waves.

Units of Chapter 14 – Keywords

• Heat As Energy Transfer
• Internal Energy
• Specific Heat
• Calorimetry – Solving Problems
• Latent Heat
• Heat Transfer: Conduction
• Heat Transfer: Convection
• Heat Transfer: Radiation