Question

what does convection require that is not required by other forms of heat transfer? it requires objects to be in direct contact to transfer heat. it requires moving gas or liquid to transfer heat. it requires empty space to transfer heat.

Explanation:

• Direct contact: This is a requirement for conduction (a form of heat transfer), not convection.
• Moving gas or liquid: Convection is the transfer of heat through the movement of fluids (liquids or gases). This is a key characteristic that differentiates it from conduction (which relies on direct molecular contact in solids) and radiation (which can occur in a vacuum).
• Empty space: Radiation can occur in empty space (e.g., heat from the sun reaching the Earth through the vacuum of space), while convection requires a fluid medium (gas or liquid).

Answer:

It requires moving gas or liquid to transfer heat.