🔍 Key Concepts

• Modes of heat transfer: conduction, convection, radiation • The role of direct contact between materials in heat transfer • Difference between heat transfer through a solid vs through a fluid (liquid or gas)

💭 Think About

• Which mode of heat transfer specifically requires objects to be touching each other for energy to pass between them? • Think about how a metal spoon gets hot when one end is in a pot of boiling water—what type of heat transfer is that? • Which of the listed options are actually modes of heat transfer, and which is a phase change rather than a heat transfer mechanism?

✅ Before You Answer

• Identify which options are true heat transfer mechanisms and eliminate the one that is a phase change instead. • Among the remaining heat transfer modes, decide which one depends on particle-to-particle contact rather than movement of the fluid or electromagnetic waves. • Recall: solids mainly transfer heat by this mechanism—match that idea to the correct term in the choices.