Question

Since the beginning of time (well, at least since the beginning of thermostat-guided heating and cooling), parents have been shouting "Don't hold the door open!" to slow-moving children in the winter months. Why? CAREFULLY explain your answer specifically in terms of Le Chatelier's Principle.

Answer 1

Le chatliers principle:

it state that a change in any of the factors that govern the equilibrium conditions of the system will cause the system to change in such a manner so as to reduce the effect of the change.

  simple saying system always try to be in equilibrium

now if we come to our activity, generally in winter months outside temperature is low compared to inside temperature in our home. when we are opening the door the outside and inside atmosperes come in to contact, but they are at different temperatures to attain equilibrium some of the heat from inside the room flows to outside. resulting decreasing temperature in side the room.

so we feel cold. thats why  parents have been shouting "Don't hold the door open .