What is atmospheric pressure? How can we calculate it?

Pressure exerted by means of an Earth's atmosphere.

Explanation:

Atmospheric pressure is also termed as barometric pressure, that is the pressure exist in the Earth's atmosphere, in other words it is the pressure wielded by the atmosphere's weight.

1 atmosphere = 760 mm Hg

Atmospheric pressure could be measured using the equation,

Atmospheric pressure = Mercury's density * acceleration through gravity * the height of mercury column.

It can be measured or given in terms of Pa, torr. atm, psi, mm Hg and so on.