Proper velocity Proper velocity In relativity, proper velocity, also known as celerity, is an alternative to velocity for measuring motion. Whereas velocity relative to an observer is distance per unit time where both distance and time are measured by the observer, proper velocity relative to an observer divides observer-measured distance by the time elapsed on the clocks of the traveling object. Proper velocity equals velocity at low speeds. Proper velocity at high speeds, moreover, retains many of the properties that velocity loses in relativity compared with Newtonian theory. For example, proper velocity equals momentum per unit mass at any speed, and therefore
This Is What Rock n' Roll Looks Like instead, the classroom setting was criticized while the presence of Lil Wayne was appreciated. The song was also used in the 2013 film, "The Smurfs 2". This Is What Rock n' Roll Looks Like "This Is What Rock n' Roll Looks Like" is the debut single of American industrial singer-songwriter Porcelain Black, featuring American rapper Lil Wayne. This song serves as the lead single from the singer's debut studio album, "Mannequin Factory". Produced by Moroccan-Swedish producer RedOne, who had originally discovered Black, "This Is What Rock n' Roll Looks Like" is influenced by the genre of rock, lyrically stating how