(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

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, 1.0 m below your arm?

(b) What is the book's speed relative to you when it hits the elevator floor?

2. Relevant equations

v = v0 + a*t

x = x0 + v0 *t + 1/2*a*t^2

x= x0 + v*t-1/2*a*t^2

V^2 = v0^2 +2*a*(x-x0)

3. The attempt at a solution

I tried to solve for time by first solving for final velocity using V^2 = v0^2+2*a*(x-x0) =

V^2 = (3.3m/s)^2 +2(-9.80m/s^2)(0-1m)

V^2 = 30.49 m^2/S^2

square root of 30.49 = 5.522 m/s

v = v0 +a*t

5.522 = 3.3 + (9.80)*t

t = 0.2267

part b) substract the book's velocity 5.522 - my velocity 3.3 = 2.222

I got both answers wrong. I was wondering if someone could help me explain what i did wrong? thank you so much!

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# Homework Help: Kinematics Free fall problems part 2 help

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