I was told years ago that the use of phrases involving a preposition at their end is largely an assimilation of Black American slang from the early part of the 20th Century. Bombs detonate or explode, they don't "go off." Likewise, buildings don't "burn up" or "burn down:" they simply burn, or they may burn completely, or they may be razed by fire. Alarms are armed or disarmed, activated or deactivated, or simply set. If they actually sound an alarm, they've been triggered or they sound. Almost all thoughts that are commonly expressed with these upside-down "prepositional phrases" can be expressed using other words or phrases that we seldom hear any longer. I might be completely wrong about whence these sloppy (and often incomprehensible) expressions came - hopefully one of our linguists will add to this thread, because I've always been curious about this myself.

"I don't know which is worse: ignorance or apathy. And, frankly, I don't care." - Anonymous