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ira [324]
3 years ago
9

A rock is thrown downward from the top of a 36.2-m-tall tower with an initial speed of 13 m/s. Assuming negligible air resistanc

e, what is the speed of the rock just before hitting the ground
Physics
1 answer:
vekshin13 years ago
4 0

Explanation:

u = 13m/s

s = 36.2m

a = 9.81m/s² (positive because it is acting on the same direction as the velocity)

Using Kinematics, we have v² = u² + 2as = (13)² + 2(9.81)(36.2) = 879.244m²/s². => v = 29.65m/s.

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It keeps the heat inside of the building

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A microfarad capacitor is charged via a 12v battery. there is 1 kohms resistor in series with the capacitor. how much current is
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A guitar string vibrates at a frequency of 330Hz with wavelength 1.40m. The frequency and wavelength of this sound wave in air (
bixtya [17]

Answer:

Same frequency, shorter wavelength

Explanation:

The speed of a wave is given by

v=f\lambda

\lambda=\dfrac{v}{f}

where,

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Here the frequency of the sound does not change.

But the velocity of the sound in air is slower.

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3 years ago
Suppose that a star has a spectrum that includes red, blue, and violet lines spaced in the pattern of the lines from hydrogen bu
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Answer:

It can be concluded that the star is moving away from the observer.

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The wavelength at rest for this case is 434 nm and 410 nm (\lambda_{0} = 434nm, \lambda_{0} = 410nm)

Redshift: \lambda_{measured}  >  \lambda_{0}

Blueshift: \lambda_{measured}  <  \lambda_{0}

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6 0
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A 62 pound box is on an incline. Determine the minimum force P that would result in the box starting to slide up the incline. (i
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Answer:

F > W * sin(α)

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These forces can be decomposed on their normal and tangential (to the slide plane) components.

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