Radiant heat transfers energy when it contacts which of the following?

• A. air in the room
• B. a ceiling fan
• C. a wall, desk, chair, or person
• D. water in a kettle

Answer: (C)

Radiant heat is energy that travels as waves from a hot source and is absorbed when those waves strike matter. The energy transfer happens when the radiant waves hit a surface and the material soaks up the energy, warming it. Solid surfaces like a wall, a desk, a chair, or a person readily absorb this radiation, which is why you feel warmth from a radiant heater when its waves reach you or nearby objects. Air in the room can eventually become warmer, but it’s not the primary recipient of radiant energy. A ceiling fan doesn’t absorb radiant energy to heat; it mostly moves air. Water in a kettle is heated mainly by conduction from the heating element or by steam, not by radiant heat.