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2 years ago

11

From the top of a cliff overlooking a lake, a person throws two stones. The two stones have identical initial speeds of v0 = 13.

4 m/s and are thrown at an angle θ = 30.1°, one below the horizontal and one above the horizontal. What is the distance between the points where the stones strike the ground?

1 answer:

Alina [70]2 years ago

8 0

Answer:

X = 15.88 m

Explanation:

Given:

Initial Velocity V₀ = 13.4 m/s

θ = 30.1 °

g = 9.8 m/s²

To Find horizontal distance let "X" we have to time t first.

so from motion 2nd equation at Height h = 0

h = V₀y t + 1/2 (-g) t ² (ay = -g)

0 = 13.4 sin 30.1° t - 0.5 x 9.81 x t² (V₀y = V₀ Sin θ)

⇒ t = 1.37 s

Now For Horizontal distance X, ax =0m/s²

X = V₀x t + 1/2 (ax) t ²

X = 13.4 m × cos 30.1° x 1.37 s + 0

X = 15.88 m

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Which equation describes the line containing the points (-2, 3) and (1, 2)

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$y = \frac{ - 1}{3}x + \frac{7}{3}$

Explanation:

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You are working as an assistant to an air-traffic controller at the local airport, from which small airplanes take off and land.

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Answer:

d = 2021.6 km

Explanation:

We can solve this distance exercise with vectors, the easiest method s to find the components of the position of each plane and then use the Pythagorean theorem to find distance between them

Airplane 1

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cos 25 = x / r

sin 25 = z / r

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z₁ = 18 103 sin 25 = 7,607 103 m= 7607 m

2 plane

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x₂ = 20 103 cos 25 = 18.126 103 m = 18126 m

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The distance between the planes using the Pythagorean Theorem is

d² = (x₂-x₁)² + (y₂-y₁)² + (z₂-z₁)²2

Let's calculate

d² = (18126-16314)² + (1100-800)² + (8452-7607)²

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2 years ago

Students in an introductory physics lab are performing an experiment with a parallel-plate capacitor made of two circular alumin

Zarrin [17]

Answer:

$\rm 9.186\times 10^{-7}\ C.$

Explanation:

<u>Given:</u>

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When the dimensions of the plate of the capacitor is comparatively much larger than the distance of separation between the plates, then, according to the Gauss' law of electrostatics, the value of the electric field strength in the region between the plates of the capacitor is given by

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where,

$\rm \sigma$ = surface charge density of the plate of the capacitor = $\dfrac qA$ .

$\rm q$ = magnitude of the charge on each of the plate.
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For the minimum value of electric field that produces spark,

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It is the maximum value of the magnitude of charge which can be added up to each of the plates of the capacitor.

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2 years ago

If the coefficient of friction is 0.3900 and the cylinder has a radius of 2.700 m, what is the minimum angular speed of the cyli

Aleks04 [339]

Answer:

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$RPM=\frac{w}{2\pi }*60\\RPM=\frac{3.05\frac{rad}{s}}{2\pi}*60\\RPM= 0.498*60\\RPM=29.88$

So you need about 30 RPM to keep people from falling out the bottom

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3 years ago