Homework

SAR stands for Specific Absorption Rate which is the unit of measurement for the amount of RF energy absorbed by the body when using a mobile phone.

Specific Absorption Rate (SAR) is a measure of the amount of RF power deposited in the human head or body whenever a mobile phone or other wireless radio device transmits. It is the maximum SAR value (in units of Watts/kilogram) that is measured during SAR compliance testing.

Chlorofluorocarbons (CFCs) are nontoxic, nonflammable chemicals containing atoms of carbon, chlorine, and fluorine. They are used in the manufacture of aerosol sprays, blowing agents for foams and packing materials, as solvents, and as refrigerants. CFCs are classified as halocarbons, a class of compounds that contain atoms of carbon and halogen atoms. Individual CFC molecules are labeled with a unique numbering system

Ultraviolet is a form of electromagnetic radiation with wavelength from 10 to 400 nm, shorter than that of visible light, but longer than X-rays. UV radiation is present in sunlight, and constitutes about 10% of the total electromagnetic radiation output from the Sun.

Sound wave is a vibration that is transmitted through a medium, such as air, water, and metals. Ultrasonic wave is defined as “inaudible sound with high frequency for human” the frequency of which generally exceeds 20 kHz. These days, sound wave which is not intended to be heard is also called ultrasonic wave.

A greenhouse gas is a gas that absorbs and emits radiant energy within the thermal infrared range, causing the greenhouse effect. The primary greenhouse gases in Earth's atmosphere are water vapor, carbon dioxide, methane, nitrous oxide, and ozone.