Convection currents.
temperature
Electro motive Force(E.M.F) of a battery determine the direction of Flow of Charges.
Heat flows towards cold.
Convection currents.
When both temperatures are the same, heat does NOT flow between objects.
human
A heat engine uses energy to work and exhaust heat that can't be used. Thermodynamics constrain the operation of a heat law and apply the conservation of energy to the system while limiting the possible efficiency of the machine to determine the direction of flow.
If your talking about fluid or air heat rises.
The heat will transfer to the cooler object.
Heat flows from the water to the ice.
Heat will naturally flow from hotter to colder objects.
A. Into the beaker