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3 years ago

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You are walking in Paris alongside the Eiffel Tower and suddenly a croissant falls on your head and knocks you to the ground. If

you neglect air resistance, calculate how many seconds the croissant dropped before it knocked you over if the velocity is 76.4 m/s.

2 answers:

Alexxandr [17]3 years ago

6 0

Answer:

7,79 seconds

Explanation:

${\overline {a}}={\frac {\Delta v}{t}}$

You need to use the acceleration formula. A is acceliration, $\displaystyle \Delta \mathbf {v}$ is change in velocity and t is time.

You need to multiply the formula with t and divide by a and you get

a*t= $\displaystyle \Delta \mathbf {v}$

t= $\displaystyle \Delta \mathbf {v}$ /a

after that you just need to insert the numbers

change in velocity is 76.4 minus 0.

acceliration is gravitational acceleration which is 9.81.

After that you get

t=76.4/9.81

t= 7,787971458 s

egoroff_w [7]3 years ago

6 0

Answer:

seconds of freefall and calculate the velocity at impact in mi/hr. I VE = 10.78 m/s ... You are walking in Paris alongside the Eiffel Tower and suddenly a croissant smacks you on the head and knocks you to the ground. From your handy ... If you neglect air resistance, calculate how many seconds the croissant dropped before it.

Explanation:

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Solve for $y_{\rm max}$ and we find that the rocket reaches a maximum altitude of about 1930 m.

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b)

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c)

The period of the orbit is given by the circumference of the orbit divided by the velocity:

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$R=6.37\cdot 10^6 m$

$h=2.60\cdot 10^6 m$

v = 6668 m/s

Substituting,

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d)

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T = 8452 s

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e)

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$R=6.37\cdot 10^6 m$

$h=2.60\cdot 10^6 m$

Substituting, we find

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Learn more about gravitational force:

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