- Thread starter
- #1

I have no clue how to solve this.

I used the usual method without integration and got s=1700m. The textbook ans says 1690.

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- Thread starter
- #1

I have no clue how to solve this.

I used the usual method without integration and got s=1700m. The textbook ans says 1690.

- Mar 1, 2012

- 935

$d=1690$m to three significant figures

- Thread starter
- #3

Thank you!

$d=1690$m to three significant figures

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- #4

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- #5

I don't understand the last part.

$d=1690$m to three significant figures

I get s1 for the interval between 0 and 6= 25.92m

Constant velocity, v=s/t, I get s2 for interval between 6 and 156= 1620m.

- Mar 1, 2012

- 935

recall the kinematics equation for uniform acceleration …

$\Delta x = v_{avg} \cdot \Delta t = \dfrac{1}{2}(v_0 + v_f) \cdot \Delta t = 4.5(10.8 + 0) = 48.6$ m

you could also use …

$\Delta x = v_0 \Delta t + \dfrac{1}{2}at^2 = 10.8 \cdot 9 - 0.6 \cdot 9^2 = 48.6$ m

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- #7

Thanks a lot!!uniformdeceleration, $\Delta t = 9$ sec.

recall the kinematics equation for uniform acceleration …

$\Delta x = v_{avg} \cdot \Delta t = \dfrac{1}{2}(v_0 + v_f) \cdot \Delta t = 4.5(10.8 + 0) = 48.6$ m

you could also use …

$\Delta x = v_0 \Delta t + \dfrac{1}{2}at^2 = 10.8 \cdot 9 - 0.6 \cdot 9^2 = 48.6$ m