Speed of Sound in Materials

No! space is a vacuum, meaning it has no particles. Sound is a mechanical wave that requires a medium to vibrate. Therefore, space is completely silent.

Because steel is much more elastic (stiff) than air. Even though steel is denser (which usually slows sound down), its extreme stiffness forces atoms to snap back into place instantly, transmitting the wave energy ~17 times faster than air.

Mach 1 is the speed of sound flowing through a fluid. In air at sea level (20°C), Mach 1 is approximately 343 m/s or 767 mph. Mach 2 is twice that speed.

In gases, higher temperatures mean faster sound. As molecules heat up, they move faster and collide more frequently, transmitting the wave pulse more quickly. Sound speed increases by about 0.6 m/s for every degree Celsius.

When an object travels faster than sound (Mach > 1), it outruns the sound waves it creates. These waves bunch up into a single shockwave cone trailing behind the object, creating a massive explosion-like noise.

It is critical for Sonar technology. Submarines and ships use sound pulses to map the ocean floor or detect other vessels. In seawater, sound travels at about 1500 m/s—over 4 times faster than in air.

In solid diamond, sound travels at about 12,000 m/s. However, the theoretical upper limit for sound speed in atomic hydrogen is about 36,000 m/s.

Yes, slightly! Humid air is actually less dense than dry air (water vapor molecules are lighter than N2/O2 molecules). Less density means less inertia, so sound travels slightly faster in humid conditions.

Helium is much less dense than air, so sound travels through it nearly 3x faster (965 m/s). This changes the resonant frequencies of your vocal tract, amplifying the higher pitches of your voice.

No. It changes constantly based on the medium, temperature, pressure (in non-ideal gases), and humidity. The value 343 m/s is just a convenient standard for air at 20°C.