When we blow air a sound will be produced why?

Question

why is whistle caused

Answer 1

Sound is just air vibrating...moving back and forth rapidly.  When you blow just right, the air passing through your lips causes the air to vibrate.  It's that simple.

You probably recognize that you don't always make a sound (whistle) every time you blow.  That's because the vibrations cancel each other out; so there is no sound.  Change the way your lips are shaped and the whislte comes back.  That's because the vibrations do not cancel out; in fact they reinforce each other.

Vibrations reinforce each other when they are standing vibrations.  This simply means they stay in one place while vibrating.  That's why your lips have to be formed just so; otherwise the vibrations move on and cancel each other out; so that's why they don't reinforce to form your whistle.

Good question.

Answer 2

Human whistling is the production of sound by means of a constant stream of air from the mouth. The air is moderated by the tongue, lips, teeth, or fingers to create turbulence, and the mouth acts as a resonant chamber to enhance the resulting sound, thus acting as a type of Helmholtz resonator. Whistling can also be produced by hands, or using an external instrument, such as a whistle or a blade of grass.

Non-instrumental whistling from the mouth can be accomplished in several ways:

Pucker (or "pursed lip") whistling, in which the air is expelled or inhaled through pursed lips, producing turbulence

Roof or palatal whistling, in which the turbulence is produced by air being pushed between the tongue and the roof (palate or alveolar ridge) of the mouth

Finger whistling or wolf-whistling, in which one or more fingers are inserted into the mouth to shape the opening, allowing a much more forceful stream of air to be blown through. A variation entails pinching at the center of the bottom lip, and sucking in, rather than blowing out, resulting in a very loud and piercing whistle.

Hand whistling, in which air is blown from the mouth into a resonant chamber formed by cupped hands

Throat whistling, in which air is blown through the throat with the mouth closed

A whistled tone is primarily a simple oscillation (or sine wave) produced in the resonant chamber, and thus timbral variations are slight. The pitch of a whistle can be altered by changing the volume and shape of the resonant chamber (most typically by using the tongue).

In duotone whistling, use of the lips and tongue are combined to produce two tones at once, which can also start and stop at different times, but must be close in pitch. Simple duets can be whistled solo in this way.

It is also possible to whistle and hum at the same time. With enough practice, it is possible for one to hum and whistle two separate melodies at the same time. One of the most prolific "hum-whistlers" is A.J. Johnson, of Leeds, who, in recent years, has appeared in a number of West End and Yorkshire-based plays demonstrating his craft with a live orchestral backdrop.

Some languages and code languages use whistles as a part of their communication; this is referred to as whistled speech.

"Loud whistling" is a non-musical type of whistling that used to indicate both satisfaction and displeasure, usually at, but not limited to, sporting events, political rallies, social gatherings, and movies. It is also used as an attention-getter for such purposes as calling dogs, flagging down taxis and alerting bus passengers in India. This piercing style of whistling is very loud and the sound can carry very far. It can be made in a number of ways with and without use of the fingers.

One specific type of whistling called "wolf-whistling" can also be used to denote physical attractiveness in the one being whistled at. Though it was frequently heard in cartoons and films of the 50s and 60s, it is now considered very poor manners in the Western world, and can even be considered a form of harassment in a professional setting. The usual setting is a man whistling at an attractive woman, but it can happen between virtually anyone. It may also be used jokingly as a compliment between closer individuals, in a romantic relationship, for example. It can also be directed to inanimate objects to signify appreciation, as with impressive buildings, or high-powered cars. The wolf-whistle usually consists of a pitch-bend up, a brief stop, followed by a quick pitch-bend up that smoothly comes back down in a continuous manner.