Elevator going down and you drop a book

AI Thread Summary
While descending in an elevator at a constant speed of 3.3 m/s, a book is dropped from a height of 1.1 m. To determine how long it takes for the book to reach the elevator floor, the correct kinematic equations must be applied. The initial attempt at calculations yielded incorrect results, indicating confusion over the appropriate formulas and values. For the final speed of the book upon impact, the speed of the elevator needs to be added to the speed calculated from the kinematic equations. Proper understanding of motion equations is essential for accurate results in this scenario.
kmiller
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Homework Statement



While riding on an elevator descending with a constant speed of 3.3 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, 1.1 m below your arm?
s
(b) What is the book's speed (relative to the earth) when it hits the elevator floor?


The Attempt at a Solution



4.9m/9.8m/s2=14.7
squareroot 14.7=3.834=answer a

1.1m+1/2(13.1)t
t=7.65
1.1m/7.65s=.1437=answer b

both of these answers were wrong. what equations am ia supposed to use?
how do i start?
 
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For the first part it looks as though you're trying to use the correct equation but I have no idea where you got your numbers from?

For part b it will just be the speed of the elevator added to the speed you work out from standard kinematic equations.
 

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