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4 years ago

11

A maple tree seed fell 180 centimeters straight toward the ground at a constant velocity. It moved that distance in 1.5seconds.

As the seed fell, a butterfly flew past it at 220 centimeters per second. What was the seed's velocity?

1 answer:

denis23 [38]4 years ago

7 0

Answer: 1.2 m/s

Explanation:

Velocity $V$ is defined as the variation of position of an object or body in time. So, if we know the distance the seed traveled and the time, we can calculate its velocity:

$V=\frac{d}{t}$

Where:

$d=180 cm \frac{1 m}{100 cm}=1.8 m$ is the distance the maple seed traveled

$t=1.5 s$ is the time

Then:

$V=\frac{1.8 m}{1.5 s}$

$V=1.2 m/s$ This is the seed's velocity

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Explanation:

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So then our linear model would be

$\rho (r)=\rho_{center}+\frac{\rho_{surface}-\rho_{center}}{r_{earth}}r$

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Replacing dV we have the following result:

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$M=\pi r^3_{earth}[\rho_{surface}+\frac{1}{3}\rho_{center}]$

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