The magnitude of atmospheric pressure is equal to the pressure exerted by a :
A. 76 mm tall column of mercury
B. 760 mm tall column of alcohol
C. 76 cm tall column of mercury
D. 760 cm tall column of mercury
Answers
C. 76 cm tall column of mercury
Explanation:
Atmospheric pressure is the pressure exerted by the atmosphere, or rather the weight of air above a point on Earth. It can be measured using a barometer. The unit of pressure is Pascals. (pascal = Newton per square metre) As we go to a higher altitude on Earth, the weight of air above it decreases, so the pressure will also be lesser. So atmospheric pressure decreases with increasing elevation.
Atmospheric pressure is measured using a barometer. At sea level, the barometer will read a value of standard or normal atmospheric pressure, equivalent to the pressure exerted by 760 mm tall column of mercury.
Option C is the answer.
Answer: c) 76 cm tall column of mercury
Explanation: The standard temperature and pressure (STP), refers to nominal conditions in the atmosphere at sea level, which supports 760 millimetres in a mercurial barometer (760 mm Hg)