🔍 Key Concepts

• Heat transfer mechanisms: conduction, convection, radiation • Physical contact vs. no contact in heat transfer • How heat moves through solids, liquids, and gases

💭 Think About

• Ask yourself: Which process requires two objects or substances to be touching each other for heat to flow? • Which process can occur through empty space (like heat from the sun reaching Earth)? Eliminate that option. • Which process involves the movement of a fluid (liquid or gas) carrying heat with it?

✅ Before You Answer

• Identify which option describes heat transfer by direct molecular contact. • Identify which option describes heat transfer that can occur through a vacuum (no matter present). • Identify which option involves bulk movement of a fluid rather than direct contact.