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This is a really basic problem but the answers I've gotten don't match up with the back of the book. I've been over it several times & can't understand where I'm going wrong - any pointers would be much appreciated!

A physics book slides off a horizontal tabletop with a speed of 1.40m/s. It strikes the floor in 0.320s. Ignore air resistance. Find a) the height of the tabletop off the floor; b) the horizontal distance from the edge of the table to the point where the book strikes the floor.

v

x = x

I broke up the book's initial velocity into components:

V

V

The height of the table = the magnitude of the vertical displacement y (using the top of the table as the origin):

y = y

What the book gives for this is 1.13m.

The horizontal distance = magnitude of horizontal displacement x:

x = x

What the book gives here is 0.502m (which is what I got for the height - which means I'm either completely mixed up or maybe the book is wrong?!)

Thanks for taking a look.

1. Homework Statement1. Homework Statement

A physics book slides off a horizontal tabletop with a speed of 1.40m/s. It strikes the floor in 0.320s. Ignore air resistance. Find a) the height of the tabletop off the floor; b) the horizontal distance from the edge of the table to the point where the book strikes the floor.

## Homework Equations

v

_{f}= v_{i}+ atx = x

_{i}+ v_{i}t + ½at^{2}## The Attempt at a Solution

I broke up the book's initial velocity into components:

V

_{f-x}= V_{i-x}= 1.40m/sV

_{f-y}= V_{i-y}+at = -gt = -3.14m/sThe height of the table = the magnitude of the vertical displacement y (using the top of the table as the origin):

y = y

_{i}+ V_{i-y}t + ½at^{2}= 0 + 0 + ½(-9.8m/s^{2})(0.320s)^{2}= -0.502m -> height = 0.502mWhat the book gives for this is 1.13m.

The horizontal distance = magnitude of horizontal displacement x:

x = x

_{i}+ V_{i-x}t + ½at^{2}= 0 + (1.40m/s)(0.320s) + 0 = 0.448mWhat the book gives here is 0.502m (which is what I got for the height - which means I'm either completely mixed up or maybe the book is wrong?!)

Thanks for taking a look.

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