Frequency is the number of occurrences of a repeating event per unit time. It is also referred to as temporal frequency, which emphasizes the contrast to spatial frequency and angular frequency. The period is the duration of time of one cycle in a repeating event, so the period is the reciprocal of the frequency. For example, if a newborn baby's heart beats at a frequency of 120 times a minute, its period – the interval between beats – is half a second (60 seconds (i.e., a minute) divided by 120 beats). Frequency is an important parameter used in science and engineering to specify the rate of oscillatory and vibratory phenomena, such as mechanical vibrations, audio (sound) signals, radio waves, and light.
For cyclical processes, such as rotation, oscillations, or waves, frequency is defined as a number of cycles per unit time. In physics and engineering disciplines, such as optics, acoustics, and radio, frequency is usually denoted by a Latin letter f or by the Greek letter or ν (nu) (see e.g. Planck's formula).
The period, usually denoted by T, is the duration of one cycle, and is the reciprocal of the frequency f:
Frequency is a music video game developed by Harmonix and published by SCEA. It is the first major release from Harmonix. It was released in November 2001. A sequel titled Amplitude was released in 2003.
In the game, a player portrays a virtual avatar called a "FreQ", and travels down an octagonal tunnel, with each wall containing a musical track. These tracks contain sequences of notes. As the player hits buttons corresponding to the note placement on the track, the "sonic energy" from within is released and the music plays. If the player plays two measures of the track without any errors, the track is "captured" and the music plays automatically until the next pre-determined section of the song. All songs featured in the game are edited for ease of play.
Some tracks are bonus tracks and only open up when all notes are played, allowing the user to pick up "freestyle" points. Powerups are available which allow the immediate capturing of the track or the doubling of points. If a player continually misses notes, their energy meter reduces until the game is over.
In physics, sound is a vibration that propagates as a typically audible mechanical wave of pressure and displacement, through a medium such as air or water. In physiology and psychology, sound is the reception of such waves and their perception by the brain.
Acoustics is the interdisciplinary science that deals with the study of mechanical waves in gases, liquids, and solids including vibration, sound, ultrasound, and infrasound. A scientist who works in the field of acoustics is an acoustician, while someone working in the field of acoustical engineering may be called an acoustical engineer. An audio engineer, on the other hand is concerned with the recording, manipulation, mixing, and reproduction of sound.
Applications of acoustics are found in almost all aspects of modern society, subdisciplines include aeroacoustics, audio signal processing, architectural acoustics, bioacoustics, electro-acoustics, environmental noise, musical acoustics, noise control, psychoacoustics, speech, ultrasound, underwater acoustics, and vibration.
He's lived as long as he possibly can
Given the circumstance
'Cause he's protected himself from the world
He never gave it a chance
And he says, "Here in my security
I've put a limit on my self-potential and my possibility"
She's seen these walls and they never change
Everything's in its place
Her relationships are neatly arranged
Down to religion and race
And she says, "Here in my security
I don't make a move unless my friends approve
I do what's expected of me"
And as I grow older
And there's so much that I do not know
I'm drawn to those who are bolder
And go where no one dare to go
And I sleep and I dream of the person I might have been
And I'll be free again
And I'll speak like someone who's been to the highest peaks
And back again
And I swear that my grass is greener than anyone's
'Til I believe again
Then I wake and the dream fades away and I face the day
And then realize that there's got to be some hero in me
There's got to be some hero in me
There's got to be some hero in me
There's got to be some hero in me
They've been suppressing their every desire
They do nothing on a whim
She's lost her sparkle and he's lost the fire
Their future looks very dim
And I say, "Here in my security
I've simply let myself go, I've developed a co-dependency"
And as I grow older
So many places that I've never been
Well, time's tappin' my shoulder
I hope it's never too late to begin, yeah
And I sleep and I dream of the person I might have been
And I'll be free again
And I'll speak like someone who's been to the highest peaks
And back again
And I swear that my grass is greener than anyone's
'Til I believe again
Then I wake and the dream fades away and I face my day
And then realize that there's got to be some hero in me
There's hero in you and in me
That sometimes it's so hard to see, yeah