Question

describe simple barometer and explain how would you use it to measure atmospheric pressure​

Answer 1

That pressure is called atmospheric pressure, or air pressure. It is the force exerted on a surface by the air above it as gravity pulls it to Earth. Atmospheric pressure is commonly measured with a barometer. In a barometer, a column of mercury in a glass tube rises or falls as the weight of the atmosphere changes.

Answer 2

A simple barometer consists of a long glass tube (closed at one end, open at the other) filled with mercury and turned upside down into a container of mercury. The barometer works by balancing the mercury in the glass tube against the outside air pressure, just like a set of scales