Consider a house at sea level that has 2500 square feet of floor area. What is the total force that the air inside the house exerts upward on the ceiling

Total Force that the air inside the house exerts upward on the ceiling is 5.25 × 10⁶ lb

Explanation:

Force =  Atmospheric Pressure × Floor Area

Where; Standard Atmospheric Pressure = 2100 lb/ft²

            Floor Area = 2500 ft²

Substitute the data

∴ Total Force = 2100 lb/ft² × 2500 ft²

  Total Force = 5.25 × 10⁶ lb

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia