British speakers say mainly [sentry-phew-gle] when the adjective stands alone and is not followed by a noun: It's centrifugal, but they shift the main stress on to the first syllable [sen-trif-yougle] if the word comes before a noun: centrifugal force. The US pronunciation is [sen-trif-yer-gle].
Black and red recall the tunics worn by soldiers during the Napoleonic wars. Gold was added to create a flag similar to the French tricolour, a symbol of revolution. Effective date: 23 May 1949.