Answer: conduction.
Explanation:
1) A skillet or pan will be in direct contact with the food.
2) Being the skillet a solid matter, it transfers heat by conduction.
3) There are three heat transfer mechanisms: convection, conduction, radiation.
i) Convection: only happens in fluids: liquids and gases.
It is a slow mechanism and is due to the motion of the particles of fluid.
This is not the case, since the skillet is solid and the eggs are in direct contact with it. If the eggs were separated from the skillet convection might happen but it would be very slow and the eggs would take so long time to be cooked.
ii) Conduction: happens by direct contact among neighboring particles, due to their vibrations. The vibrations are only transmitted to neighboring particles, which is only possibble when they are in direct contact, so it is the classical mechanism in solids. So, the heat transfer using the skillet to cook scrambles eggs is an example of conduction.
iii) Radiation: is the transfer of heat by infrared waves. It is an important mechanism when the substances are separated by vaccum or gases and the difference of temperature is high. Yet, this is not the importante mechanism here. You feel heat radiation when you put your hand close to the skillet.
