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Heat is the transfer of energy from a hot object to a colder object.[1] There are two types of heat: sensible and latent heat, and three types of heat transfer: convection, conduction, and radiation.[2]

Heat types

Sensible heat is when heat is applied to a substance merely raises its temperature, but does not cause a phase change. It is the heat, which added or subtracted from a substance, that produces a change in temperature that is indicated on a thermometer. It is the heat that you feel or sense.[3]

Latent heat is the heat released or absorbed by a substance when it changes its physical state to another without changing its temperature. Latent heat of fusion is the process of converting from a liquid to a solid or a solid to a liquid and latent heat of vaporization is the conversion of a liquid to a vapor or vapor to a liquid. The latent heat of vaporization phenomenon is the founding principle in refrigeration and air conditioning and is known as the cooling effect.[3] There is also latent heat of sublimation, but is less applicable.

Heat transfer types

Convection is the heat of a fluid substance, such as air or liquid, that then travels away from its heat source and carries its thermal energy along.[4]

Conduction is the transfer of heave via direct molecular collision.[4]

Radiation is the transfer of heat through electromagnetic waves.[4]