Final answer:
The correct formula for calculating air exchange rate per hour at a given pressure difference is Q = C∆P^n, relating to physics and specifically thermodynamics and fluid mechanics.
Step-by-step explanation:
The question provided deals with the air exchange rate in a building, which is particularly relevant in the field of physics, specifically within the subject of thermodynamics and fluid mechanics. The correct formula to calculate the air exchange rate per hour when a forced air pressure difference is present is Q = C∆P^n. Here, 'Q' represents the volume flow rate (the amount of air flowing per unit time), 'C' is the flow coefficient related to the properties of the building and the conditions of the test, 'P' represents the pressure difference, and 'n' is the flow exponent, which depends on the flow regime (laminar or turbulent).
When it comes to improving airtightness in residential construction, strategies such as weather stripping, caulking, and enhanced window seals are employed. This is to increase the turnover time of the air, leading to increased energy efficiency and better control over the indoor environment.