What are the three modes of heat transfer?

The three modes of heat transfer are indeed convection, conduction, and radiation.

Conduction involves the transfer of heat through a material without any motion of the material as a whole. It occurs at the microscopic level as kinetic energy is passed through collisions between neighboring particles. This is the mechanism by which heat travels through solids, such as a metal rod being heated at one end while the other end gets warm over time.

Convection, on the other hand, refers to heat transfer that occurs in fluids (liquids and gases) through the movement of the fluid itself. As a fluid is heated, it becomes less dense and rises, while cooler fluid moves in to take its place, creating a circulation pattern. This is commonly observed in boiling water or the heating of air in a room.

Radiation is the transfer of heat in the form of electromagnetic waves, such as infrared radiation. Unlike conduction and convection, which require a medium, radiation can occur in a vacuum. This is how the Sun warms the Earth, despite the vast empty space between them.

Understanding these modes of heat transfer is fundamental in fields such as thermodynamics, mechanical engineering, and many applications in everyday life. The other options either mix elements that do not primarily describe heat transfer processes