GK
UNITS DEVICES DIMENSIONS AND MEASUREMENTS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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0.1 m
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0.01 m
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0.1 mm
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0.01 mm
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Detailed explanation-1: -One Dobson Unit is the number of molecules of ozone that would be required to create a layer of pure ozone 0.01 millimeters thick at a temperature of 0 degrees Celsius and a pressure of 1 atmosphere (the air pressure at the surface of the Earth).
Detailed explanation-2: -This depleted region is known as the “ozone hole”. The area of the ozone hole is determined from a map of total column ozone. It is calculated from the area on the Earth that is enclosed by a line with a constant value of 220 Dobson Units.
Detailed explanation-3: -Dobson Units (DU), a measure of the thickness of the ozone layer by an equivalent layer of pure ozone gas at normal temperature and pressure at sea level. This means that 100 DU=1mm of pure ozone gas at normal temperature and pressure at sea level.
Detailed explanation-4: -Accordingly, the unit of measure for total ozone is called the “Dobson unit” (see Q4).