08/09/2025
Description: "Breaking the sound barrier" is a term used to describe the moment when an object (like a jet or spacecraft) travels faster than the speed of sound in air.
What is the Speed of Sound?
The speed of sound in dry air at sea level is about:
343 meters per second
1,235 kilometers per hour
767 miles per hour
This speed can change depending on altitude, temperature, and air pressure.
What Happens When You Break the Sound Barrier?
When an aircraft goes faster than sound:
1. Shock waves form in the air.
2. These shock waves create a sonic boom — a loud explosive sound.
3. The plane transitions from subsonic (< Mach 1) to supersonic (> Mach 1) speed.
Mach 1 is the speed of sound in a given medium—typically air. It's used as a reference point for measuring supersonic and hypersonic speeds.
Mach number is a dimensionless unit that compares the speed of an object to the speed of sound.
Mach 1 in Air:
At sea level and at 20°C (68°F), Mach 1 ≈ 343 meters per second (m/s) or 1235 kilometers per hour (km/h) or 767 miles per hour (mph).
The speed of sound isn't constant—it varies with temperature, altitude, and the medium (air, water, etc.).
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