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## Homework Statement

A point begins at rest at x = 0 and accelerates at 1.09 m/s^2 to the right for 10 s. It then continues at constant velocity of 10.9 m/s for 8 more seconds. In the third phase of its motion, it decelerates at 5 m/s^2 and is observed to be passing again through the origin when the total time of travel equals 28 s. Determine the whether or not the particle has passed returned to the origin.

## Homework Equations

## The Attempt at a Solution

I am splitting up the motion into the 3 phases mentioned.

a1 = 1.09 ∴

**v1 = 1.09t**

**v2 = 10.9**

a3 = -5 ∴ v3 = -5t + c → v3(0) = v2(8) = 10.9 ∴

**v3 = -5t + 10.9**

Now I will get the displacements by integrating all of the velocity equations over their respective time intervals.

r1 = ∫v1 from 0 to 10 = 54.5

r2 = ∫v2 from 0 to 8 = 87.2

r3 = ∫v3 from 0 to 10 = -141

Adding all of the displacements,

**r1 + r2 + r3 = 0.7 therefore the particle is almost at the origin but hasn't passed it again...**

I don't know the correct answer but I know I am wrong... Am I going about this correctly?