Candela was chosen so that the new definition would precisely match the old definition. Although the candela is now defined in terms of the second (an SI base unit) and the watt (a derived SI unit), the candela remains a base unit of the SI system, by definition. If a source emits a known luminous intensity "I" (in candelas) in a well-defined cone, the total luminous flux "Φ" in lumens is given by where "A" is the "radiation angle" of the lamp—the full vertex angle of the emission cone. For example, a lamp that emits 590 cd with a radiation angle
P.S.K. What Does It Mean? was first used on the song "Rock 'N' Roll" which later became "You'll Be Under My Wheels". The second time they used it is from a song called "Lyrical Terrorist" which later became "Serial Thrilla", but it was soon used on the album "The Day Is My Enemy". P.S.K. What Does It Mean? "P.S.K. What Does It Mean?" (also written as "P.S.K. (What Does It Mean?)") is a song released in 1985 by Philadelphia rapper Schoolly D on his independent label Schoolly D Records. P.S.K. is the abbreviation for Park Side Killas, a street gang with which Schoolly D was