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zimovet [89]
3 years ago
12

If state law mandates that elevators cannot accelerate more than 4.80 m/s2 or travel faster than 19.8 m/s , what is the minimum

time in which an elevator can travel the 373 m from the ground floor to the observatory floor?
Physics
1 answer:
Rudik [331]3 years ago
8 0

Answer:

23.0 s

Explanation:

Given:

v₀ = 0 m/s

v = 19.8 m/s

a = 4.80 m/s²

Find: Δx and t

v² = v₀² + 2aΔx

(19.8 m/s)² = (0 m/s)² + 2 (4.80 m/s²) Δx

Δx = 40.84 m

v = at + v₀

19.8 m/s = (4.80 m/s²) t + 0 m/s

t = 4.125 s

The elevator takes 40.84 m and 4.125 s to accelerate, and therefore also 40.84 m and 4.125 s to decelerate.

That leaves 291.3 m to travel at top speed.  The time it takes is:

291.3 m / (19.8 m/s) = 14.71 s

The total time is 4.125 s + 14.71 s + 4.125 s = 23.0 s.

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Alchen [17]
<h2>Answer: x=125m, y=48.308m</h2>

Explanation:

This situation is a good example of the projectile motion or parabolic motion, in which we have two components: x-component and y-component. Being their main equations to find the position as follows:

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Where:

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y_{o}=0  is the initial height of the projectile (we are told it  was launched at ground level)

y  is the final height of the projectile (the value we want to find)

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x=(54.5m/s)cos(35\°)(2.8s)   (3)

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For y (2):

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The drawing shows three objects rotating about a vertical axis. The mass of each object is given in terms of m0, and its perpend
photoshop1234 [79]

Answer:

I₁ > I₃ > I₂

Explanation:

Taking the pic shown, we have

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Describe the earth's rotation on it axis
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<span>Earth's rotation is the rotation of the planet Earth around its own axis. The Earth rotates from the west towards east. As viewed from North Star or polestar Polaris, the Earth turns counter-clockwise.</span>
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kenny6666 [7]

Answer:

Hello your question is incomplete attached below is the complete question

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