Final answer:
When the door to your house is opened, colder air enters due to convection, which is the movement of heat through fluid movement, and this is also accompanied by smaller contributions from conduction and radiation.
Step-by-step explanation:
When you open the door to your house and feel a rush of cold air, the form of heat transfer involved is primarily convection. This occurs because the warmer air inside your house, which is less dense, rises and is replaced by the denser, cooler air from outside. This natural movement of air due to differences in temperature and density is a characteristic of convection, where a fluid such as air or water moves and carries heat along with it.
In addition to convection, conduction and radiation might also play roles in transferring heat in your scenario. Conduction could occur as the colder outdoor air contacts the warmer air or surfaces inside your house. Radiation occurs when heat is transferred through electromagnetic waves, which can happen when warmer objects inside your home lose heat to the cooler incoming air.