Swamp coolers are effective because . A. the water is colder than the air.
B. the water pulls heat from the room to undergo a phase change.
C. the thermal energy of the water is decreasing.
D. the water's latent heat of vaporization is being pulled from the air.

D. the water's latent heat of vaporization is being pulled from the air.

Explanation:

A swamp cooler also generally referred to as the evaporative cooler is an electronic device that uses moisture to cool air. This simply means that, the electronic device works on the principle of evaporation of water to cool the surrounding air.

In swamp coolers, water absorbs large amount of warm air via the evaporative wet cooler pad, so as to evaporate and consequently cooling the air effectively and efficiently.

Swamp coolers are effective because the water's latent heat of vaporization is being pulled from the air.

The latent heat of vaporization can be defined as the energy that is being absorbed by water during evaporation.

The swamp coolers are typically made up of the following essential components, these are;

1. Float.

2. Blower.

3. Pump.

4. Evaporative pad.

5. Water supply valve.

Hence, through the principle of evaporative cooling (latent heat of vaporization), swamp coolers reduces or lower the air temperature in its surroundings.

explanation:

the masses of the objects and the distance between them

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