why does the engine of motor verhicles emit a buzzing sound instead of continuous small booms?

Question

why does the engine of motor verhicles emit a buzzing sound instead of continuous small booms?

In: Engineering

Answer 1

Most passenger automobiles idle at between 600 and 1000 rpm. That is revolutions of the crank shaft so in a 4 cylinder engine each cylinder will have a detonation within it for every revolution. This means 2400 to 4000 explosions a minute, or 40-66 per second.

That speed of little booms tends to blend together into a buzzing or hum.