Which of the following is not an example of convection heat transfer?

Convection heat transfer refers to the process where heat is transferred through the movement of fluids (liquids or gases). It involves the bulk movement of the fluid itself, carrying heat with it from one location to another. In contrast, infrared heat and radiation heat refer to the transfer of energy through electromagnetic waves, which does not require a medium. These methods of heat transfer operate based on different principles: conduction involves the transfer of heat through direct contact of materials, while convection requires fluid movement.

Infrared heat, associated with radiation, is fundamentally different from convection because it can occur in a vacuum, where no fluid is present to facilitate the transfer of heat. Therefore, infrared heat does not involve the movement of a fluid, making it the correct choice for this question, as it does not exemplify convection heat transfer. Understanding these distinct modes of heat transfer helps clarify why convection is a unique process compared to infrared or radiation methods.