you need
  • calculator or Internet access.
Guide
1
Start by clarifying which of the two options is the atmospheres you need to get as a result of the conversion of the initial value in megapascals.Most often it refers to the "standard" or "physical" atmosphere, which is equal to the pressure force that can counterbalance the 760-millimeter mercury column density of 13,595.1 kg / m?the acceleration of free fall equal to 9.80665 m / s ?.These are the density of mercury at 0 ° C, and the attractive force of the Earth at sea level.But there is also a "tech
nical" atmosphere which take equal to the force of pressure in a mass of 1 kg on the plane area of ​​1 cm ?, perpendicular gravity in 1kgs.
2
Define conversion factor values ​​from MPa in atmosphere .Based on the fact that one standard atmosphere is equivalent to 101,325 Pascal and one technical atmosphere corresponds to 98,066.5 Pascal.Reduction MPa indicated by the value of the derivative of Pascal - megapascals.In all used in SI units prefix mega correspondence factor equal to one million (10?), And therefore the above values ​​should be reduced by six orders of magnitude.Transfer the comma and get rates 0.101325 and 0.0980665.
3
Divide the original value, measured in megapascals, in the conversion factor obtained in the previous step.Since this factor - not a round number, then perform calculations in my mind is not very convenient.Use a calculator for this, and if there is access to the Internet, use a calculator built into many search engines.For example, if you want to translate into physical atmosphere the pressure of 78 MPa , then go to Google's home page and the search query box, type 78 / 0.101325.The search engine will calculate and display the result: 78 / 0.101325 = 769.800148.