Doppler Typeface

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Doppler Effect As an object moves through air, it must push some of the air out of the way. But the object also creates sound waves as it moves through the air. As a moving source of sound the object causes a ‘doppler’ effect. When that object reaches the speed of sound, air cannot readily move out of the way and a shockwaves is formed. When the object is moving faster than sound, the resulting sounds travel behind the object creating a sonic boom.

Moving in air When an object such as an airplane moves through the air, it increases the frequency of the sound waves ahead of it, due to its velocity. This is the Doppler effect, where the pitch of the sound is heard as higher when the object is moving toward you and the pitch is lower, as the object moves away.

Longer Wavelength Lower Frequency

Shorter Wavelength Higher Frequency

Speed of Sound When the moving object or airplane reaches the speed of sound, it catches up to the sound waves it is creating, and they bunch up at the front end of the object, forming a shock wave. This is a reason that it is difficult for an airplane to break the sound barrier.

Shockwaves Created

Supersonic Speeds When an aircraft travels at supersonic speeds or is moving faster than sound, it leaves the sound waves it makes behind it. These waves fan out and cause a sonic boom.

Sonic Boom

Carl holderness hello@carlholderness.co.uk


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