In heat transfer, which method is based on gravitation

A) Natural convection

B) Conduction

C) Radiation

D) Stirring of liquids

Heat can be transferred in three ways:conduction, convection, and radiation. Stirring liquids is not considered a method of heat transfer.

• Conduction: Heat is transferred by direct contact between the source and the object. Molecules near the heat source become excited and transfer energy to neighboring molecules. This process does not require a gravitational field.
• Convection: Heat transfer occurs through the movement of fluid particles. Thermal energy flows from the source to the object due to temperature gradients. Since the temperature difference acts vertically, particles rise or sink depending on their density under gravity. Thus, a gravitational field is necessary for convection to occur.
• Radiation: Heat is transferred through electromagnetic waves and does not require a medium.

Correct Answer: Option A) Natural Convection