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Tuning fork pitch varies slightly with temperature, due mainly to a slight decrease in the modulus of elasticity of steel with increasing temperature. A change in frequency of 48 parts per million per °F (86 ppm per °C) is typical for a steel tuning fork. The frequency decreases (becomes flat) with increasing temperature. [6]
The radio spectrum is the part of the electromagnetic spectrum with frequencies from 3 Hz to 3,000 GHz (3 THz). Electromagnetic waves in this frequency range, called radio waves , are widely used in modern technology, particularly in telecommunication .
In frequency (and thus energy), UV rays sit between the violet end of the visible spectrum and the X-ray range. The UV wavelength spectrum ranges from 399 nm to 10 nm and is divided into 3 sections: UVA, UVB, and UVC. UV is the lowest energy range energetic enough to ionize atoms, separating electrons from them, and thus causing chemical reactions.
For other tuning schemes, refer to musical tuning. This list of frequencies is for a theoretically ideal piano. On an actual piano, the ratio between semitones is slightly larger, especially at the high and low ends, where string stiffness causes inharmonicity, i.e., the tendency for the harmonic makeup of each note to run sharp.
A440 is often used as a tuning reference in just intonation regardless of the fundamental note or key. The US time and frequency station WWV broadcasts a 440 Hz signal at two minutes past every hour, with WWVH broadcasting the same tone at the first minute past every hour. This was added in 1936 to aid orchestras in tuning their instruments. [11]
Very high frequency (VHF) is the ITU designation [1] [2] [3] for the range of radio frequency electromagnetic waves (radio waves) from 30 to 300 megahertz (MHz), with corresponding wavelengths of ten meters to one meter. Frequencies immediately below VHF are denoted high frequency (HF), and the next higher frequencies are known as ultra high ...
Experiment using two tuning forks oscillating at the same frequency.One of the forks is being hit with a rubberized mallet. Although the first tuning fork hasn't been hit, the other fork is visibly excited due to the oscillation caused by the periodic change in the pressure and density of the air by hitting the other fork, creating an acoustic resonance between the forks.
The 800 MHz frequency band is a portion of the electromagnetic spectrum, or frequency band, that encompasses 790–862 MHz.. Being a part of the spectrum known as "UHF Bands IV and V" (i.e. 470 MHz to 862 MHz) it was allocated by the ITU to Broadcasting as the primary user in Region 1 and was used for analogue television broadcasting before changing to digital terrestrial television in many ...