This number is said to be irrational because its value has an infinite number of decimal places. Another famous irrational number is pi , which is the ratio of the circumference of a circle to its diameter. The value of pi is approximately 3.142, and the value of e is approximately 2.718. Countless physical processes can be described by the number e raised to a positive or negative exponent. Such processes are said to grow or decay exponentially .
Many calculators have a function for raising e to any power.
It will be helpful if you have one of these available for making exponential atmosphere calculations. The equation says that the atmospheric pressure decays exponentially from its value at the mean surface of the body where the height h is equal to 0. The surface pressure on Earth is approximately 1 bar, and the scale height of the atmosphere is approximately 7 kilometers. With this information, you can estimate the pressure at any altitude in Earth's atmosphere using the formula from above. Make sure that you understand how the formula works and that you can correctly calculate the atmospheric pressure at an altitude of 3 kilometers in Earth's atmosphere.