Question

Ventilation in room is due to __
(a) conduction
(b) convection
(c) radiation
(d) all of these

Answer 1

Hint: The deliberate introduction of outside air into a place is known as ventilation. Ventilation is primarily used to regulate indoor air quality through dilution and displacement of interior pollutants; however, it can also be used to control indoor temperature, humidity, and air motion for thermal comfort, contentment with other aspects of the indoor environment, or other goals.

Complete answer:
The purposeful fan-driven movement of external air into a structure is known as mechanical ventilation. Supply fans (which push outside air into a building) and exhaust fans (which draw air out of a building and so produce equal ventilation flow into a structure) are two types of mechanical ventilation systems. Mechanical ventilation is frequently delivered by the same equipment that heats and cools a place.
The flow of air is required in the ventilation process, but the humidity and temperature must be maintained according to the requirements, since this permits perspiration to evaporate from the skin.
Many issues can arise as a result of inadequate ventilation, and they can impact the body by causing headaches, pain, and tiredness. The ventilation process is initiated when the amount of carbon dioxide increases while the amount of oxygen drops. Ventilation is a way of artificially assisting breathing. In addition, a mechanism to transport breathable air into and out of the body is being created.
Winds outdoors and convection currents inside a building provide natural ventilation. There are three different kinds of heat transmission. Convection is one of them, while conduction and radiation are the other two. Liquids and gases are the only things that can convect. Current molecules are free to travel in convection. Heat energy can thus be transferred. There is also a temperature differential between two sections of the fluids. Due to temperature differences, hot fluids rise and cold fluids sink, causing currents to form in the fluids.
The sinking of colder air causes convection currents, and the heavier air displaces the warmer air. As a result of the pressure decrease within the room, the air that is breathed gets warmer and then flows out via the ventilator. As a result, new air enters the room, and the process repeats again, with convection currents maintaining the room's temperature.
Hence option b is correct.

Note:
Convection is the spontaneous movement of a single or multiphase fluid caused by the combined effects of material property heterogeneity and body forces on a fluid, most frequently density and gravity. Convection owing to the effects of thermal expansion and buoyancy might be assumed when the origin of the convection is unknown.