Weightlessness

Weightlessness, or an absence of 'weight', is an absence of stress and strain resulting from externally applied mechanical contact-forces, typically normal forces from floors, seats, beds, scales, and the like. Counterintuitively, a uniform gravitational field does not by itself cause stress or strain, and a body in free fall in such an environment experiences no g-force acceleration and feels weightless. This is also termed "zero-g" where the term is more correctly understood as meaning "zero g-force."

When bodies are acted upon by non-gravitational forces, as in a centrifuge, a rotating space station, or within a space ship with rockets firing, a sensation of weight is produced, as the contact forces from the moving structure act to overcome the body's inertia. In such cases, a sensation of weight, in the sense of a state of stress can occur, even if the gravitational field was zero. In such cases, g-forces are felt, and bodies are not weightless.

When the gravitational field is non-uniform, a body in free fall suffers tidal effects and is not stress-free. Near a black hole, such tidal effects can be very strong. In the case of the Earth, the effects are minor, especially on objects of relatively small dimension (such as the human body or a spacecraft) and the overall sensation of weightlessness in these cases is preserved. This condition is known as microgravity and it prevails in orbiting spacecraft.

Zero Gravity (disambiguation)

Zero gravity refers to weightlessness.

Zero gravity may also refer to:

See also

Stunts and flights

Games

Film TV and entertainment

Music

See also

Sonic Riders: Zero Gravity

Sonic Riders: Zero Gravity, later released in Japan as Sonic Riders: Shooting Star Story (ソニックライダーズ シューティングスターストーリー, Sonikku Raidāzu: Shūtingu Sutā Sutōrī), is a hoverboard racing video game developed by Sonic Team and published by Sega. It is the fifth racing game in the Sonic the Hedgehog series, following Sonic Drift, Sonic Drift 2, Sonic R and its predecessor, Sonic Riders. A sequel titled Sonic Free Riders was released on November 4, 2010 exclusively for Kinect on Xbox 360.

Plot

The Story is split into two halves, the Heroes Story (Team Sonic), and Babylon Story (Babylon Rogues). Although the stories start separately, they overlap each other, telling the story as the main characters within that story see it. Following the format of Sonic Riders, Babylon Story also includes an epilogue that expands past the Heroes Story leading to the last course.

Sonic, Tails, and Knuckles are alerted to robots that are attacking a famous city of the future. They set out to retrieve a legendary artifact that has the ability to control gravity. Along the way they discover surprises, including the return of the Babylon Rogues, a group of avian thieves who are also after the artifacts. This sets off a war to decide who gets the artifact, leading them to settle their dispute by having an Extreme Gear competition.

Kerli

Kerli Kõiv ([ˈkerli ˈkɤ.iʋ]; born 7 February 1987), usually referred to mononymously as Kerli, is an Estonian recording artist and songwriter. Born in Elva, Estonia, Kerli entered multiple singing competitions before being signed to Island Records in 2006 by LA Reid. In 2007, she released her debut self-titled extended play and in 2008, released her debut studio album, Love Is Dead, the latter of which charted on the Billboard 200. The lead single from the album, "Walking on Air," charted in many countries and was also featured as the iTunes Store's Single of the Week where it was downloaded over 500,000 times, a record at that time. In the years following, Kerli was featured on Almost Alice with the song "Tea Party" and she began to abandon her alternative rock sound and started to adopt a more electronic and dance-influenced sound, as can be heard in her 2010 single "Army of Love".

Following the release of Love Is Dead, Kerli began production on a second studio album which became her second extended play Utopia, released in early 2013, where it became Kerli's second release to chart on the Billboard 200. Two promotional singles from the EP, "Army of Love" and "Zero Gravity", were released prior to the release of the album's first official single, "The Lucky Ones". All three songs entered the top ten of Billboard's Hot Dance Club Songs chart, two of them peaking at number one. Two songs which were co-written by Kerli for Utopia, "Skyscraper" and "I Feel Immortal", were later recorded by artists Demi Lovato and Tarja Turunen respectively. Kerli's version of "I Feel Immortal" was later released on Frankenweenie Unleashed!.

Kerli (EP)

Kerli is the debut self-titled EP by Estonian singer-songwriter Kerli. It was released on October 16, 17 through Stolen Transmission in association with the artist's label Island Records. After being signed to Island in 2006, Kerli began producing her debut album Love Is Dead and released the EP as a teaser for the album. The music from the EP is influenced by genres such as electropop and nu metal while its lyrical topics include individuality and rebellion. From the three-song release, which contains the cover of Bauhaus' "She's in Parties", "Walking on Air" and "Love Is Dead" were later included in Love Is Dead (2008). Kerli received a positive review for its musical diversity.

Background and composition

In June 2006, Estonian singer-songwriter Kerli signed a record deal with Island Records after auditioning to L.A. Reid and began the development of her then upcoming debut album Love Is Dead, whose producers include David Maurice and Lester Mendez. She released her self-titled debut extended play (EP) as a digital download through Stolen Transmission on October 16, 2007 as a teaser for Love Is Dead; a promotional CD containing the songs was also released through Island.