Question

coverter for formula to find relative pressure with relation to atmospheric pressure and absulute pressure

Answer 1

You're walking outside on a windy day and the wind is strong enough that you can feel its force. This feeling is caused by the air molecules that are bouncing off of you. We call this collective force of the air molecules per unit area the atmospheric pressure. Often, this pressure is measured in pounds per square inch (psi).

Answer 2

Add your atmospheric pressure. For example, if your atmospheric pressure is 14.7 psi and your gage reads 20 psig. The absolute pressure of your system is 34.7 psia.