How to Convert Mach 1 to MPH

A jet fighter at mach 2 is flying at twice the speed of sound.

Fast, faster, fastest. On I-95 from New York to Washington, D.C., every driver wants to go faster than every other driver. Jet fighter pilots in the air might be the same, but instead of going faster than tractor-trailers or SUVs, fighter pilots are flying faster than sound. Engineers and pilots use the term "mach" to describe the speed of a plane traveling close to or above the speed of sound. You can easily convert from mach to miles per hour (mph).

Things You'll Need

• Calculator

Instructions

1. Measure the temperature for which you want to make your conversion. For example, you use a temperature of 40 degrees Fahrenheit.

2. Add 460 to your temperature to convert your temperature to degrees Rankine. For example, 460 + 40 = 500.

3. Take the square root of the product of your temperature in degrees Rankine and 2405.2 using a calculator to determine the speed of sound at the given temperature. For example, (500 x 2405.2)^1/2 = 1096.631. The speed of sound at this temperature is 1,096.6 feet per second.

4. Multiply your answer by 0.682 to convert the speed of sound at your chosen temperature to miles per hour (mph). For example, 1096.631 x 0.682 = 747.902. The speed of sound at this temperature is 747.9 miles per hour.

5. Multiply your answer by the mach number. For example, your mach number is 1 -- 1 x 747.9 = 747.9. Mach 1 at 40 degrees Fahrenheit equals 747.9 miles per hour.

References

• Florida International University: What Is Mach Number?
• University of North Carolina, Chapel Hill; Units: M; Russ Rowlett; 2001
• Pellissippi State Community College: Chapter 12 -- Temperature and Heat
• Christian Brothers University: Temperature