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A speedboat moving at 30.0 m/s approaches a no-wake buoy marker 100 m ahead. The pilot slows the boat with a constant acceleration of -3.50 m/s^2 by reducing the throttle.

a. How long does it take the boat to reach the buoy?

b. What is the belocity of the boat when it reaches the buoy?

Equations given:

V[final] = V[initial] + AT (for constant acc.)

X[final] = X[initial] + .5(V[initial] + V[final])T

X[final] = X[initial] + (V[initial])T + .5AT^2

My pitiful attempt:

For a. : I used the third equation, assuming that my initial position would be zero, as the point from which the deceleration began, and my final position would be 100. The two results for the quadratic equation were 12.612 and 4.531.

That's where I was stuck.

I then tried b. : Utilizing the second equation, I got V^2 = 200 (m^2 - m)/(s^2)

...this just doesn't seem right, and I would really appreciate some help.

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# Homework Help: A really annoying speedboat.

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