AY Honors/Whistles/Answer Key

A party whistle.

A metal pea whistle.

A whistle is a simple Aero, instrument which produces music to the ear from a stream of forced carbon dioxide.

Many types exist, from small police and sports whistles (also called pea whistles), to much larger train whistles, which are steam whistles specifically designed for use on locomotives and ships. Although whistles have a musical

A steam whistle works the same way, but using steam as a source of pressure: such whistles can produce extremely high sound intensities.

Industrial whistles

Industrial whistles are used for signalling and timekeeping both on railroad and ships, and in factories. Most of these whistles were steam powered and not standardized. Individual locomotives could be identified by their whistles. At noontime in industrial areas up into the 1950s whistles of every pitch could be heard, as each factory had a boiler and a whistle, if not full steam power.

Railroads in particular used elaborate whistle codes for communication both within the train and with other trains. These methods are maintained today with motor-powered air horns. Trucks also use air horns, especially since they often have air brakes and so there is already a source of compressed air on board.

Train whistles generally produce three or four different frequencies at the same time to produce a non-major chord that is distinct, loud, and low in pitch.

Ship's whistles must be very loud for safety on the seas. Modern ship's whistles can be electrically or steam driven. Template:RMS was originally equipped with three electric Tyfon whistles in 1932. They could be heard at least ten miles away and were tuned to 55 Hz, a low bass A note that was chosen for maximum passenger comfort despite the high sound pressure level. One of the three whistles was taken back to Kockum Sonics in Malmö, Sweden, where it was refurbished for a new life of service aboard the RMS Queen Mary 2. Modern IMO regulations specify ships' whistle frequencies to be in the range 70-200 Hz for vessels that are over 200 meters in length. Traditionally, the lower the frequency, the larger the ship. The Queen Mary 2, being 345 meters long, was given the lowest possible frequency (70 Hz) for her regulation whistles which means she carries both 70 Hz modern whistles and a single vintage 55 Hz whistle.

Safety

Whistles are often used as warning devices or as safety devices serving to attract attention to the user. Some cyclists use a whistle as a substitute for a bell or horn. It should be noted, however, that many jurisdictions require that the warning device be permanently attached to the bicycle.

Rescue or survival whistles are often packed in survival kits and attached to personal flotation devices to allow a victim to signal for help. The whistle is audible at much greater distances than the human voice, and is less likely to cause exhaustion if used repeatedly. Survival whistles differ from pea whistles in that they are usually flat, so that water cannot collect inside if the user is immersed, for example after falling overboard from a boat.

Whistles can also produce sounds at pitches inaudible to the human ear such as dog whistles which can be heard by dogs at a range beyond that of human sensory perception, or at least conscious perception.

Sporting

Whistles are used by referees to officiate sporting matches. Some sports use different types of whistles, but one used around the world in many sports is the Fox 40, a pealess whistle which creates sound using air pressure only.

The Fox 40 is used in Basketball, Hockey, Ice Hockey, Soccer and numerous other games, as it can be heard easily over the noise of the audience.

Another whistle widely used for sports such as Touch Football, Rugby League and Rugby Union is the Thunderer 58.5 by Acme Whistles. It is a metal whistle containing a cork pea. It is used mainly because of its design that allows the user to create a deep, low-pitch shrill that can be heard from hundreds of meters away.

Music

A samba whisle with three tones

The whistle is used in samba percussion groups as a leader help to catch the percussionnist attention. The traditional samba whistle has three tones, but as the number of musicians rises in the percussion section, pealess whistles became more popular due to their high pitch and their loud sound.

External links

• Joseph Hudson & Co historydead link 29 october 2008
• Clay Whistles
• Whistle Museum