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While riding on an elevator descending with a constant speed of 3.4 m/s, you accidentally drop a book from under your arm.
(a) How long does it take for the book to reach the elevator floor, 1.2 m below your arm?
s
(b) What is the book's speed (relative to the earth) when it hits the elevator floor?
m/s
I tried coming up with a new acceleration value by subtracting 3.4 from 9.81,but I got the wrong answers. Then it dawned on my that I can't do it that way. If the elevator were decending 9.8 m/s, objects would still drop to the elevator floor because they're accelerating and the elevator is moving at a constant speed.
So... I'm lost on this one. There's an almost identical problem about a hot air balloon ascending at a constant rate, and someone throwing a camera up to someone in the balloon. But if I understand how to do the first one, I can probably come up with the other.
thanks in advance...
(a) How long does it take for the book to reach the elevator floor, 1.2 m below your arm?
s
(b) What is the book's speed (relative to the earth) when it hits the elevator floor?
m/s
I tried coming up with a new acceleration value by subtracting 3.4 from 9.81,but I got the wrong answers. Then it dawned on my that I can't do it that way. If the elevator were decending 9.8 m/s, objects would still drop to the elevator floor because they're accelerating and the elevator is moving at a constant speed.
So... I'm lost on this one. There's an almost identical problem about a hot air balloon ascending at a constant rate, and someone throwing a camera up to someone in the balloon. But if I understand how to do the first one, I can probably come up with the other.
thanks in advance...