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
What Difference Does It Make? What Difference Does It Make? "What Difference Does It Make?" is a song by the English rock band the Smiths, written by singer Morrissey and guitarist Johnny Marr. It was the band's third single and is featured on their debut album, "The Smiths". A different version, recorded for the John Peel Show on BBC Radio 1, is included in the compilation album "Hatful of Hollow". The song was one of the band's first significant chart hits, peaking at No. 12 in the UK Singles Chart. However, Morrissey has said "What Difference Does It Make?" is among his least favourite songs