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kumpel [21]
2 years ago
7

A man stands on his balcony, 130 feet above the ground. He looks at the ground, with his sight line forming an angle of 70° with

the building, and sees a bus stop. The function d = 130 sec θ models the distance from the man to any object given his angle of sight θ. How far is the bus stop from the man? Round your answer to the nearest foot.
Physics
1 answer:
jenyasd209 [6]2 years ago
8 0

Answer:

d =  380 feet

Explanation:

Height of man = perpendicular= 130 feet

Angle of depression = ∅ = 70 °

distance to bus stop from man = hypotenuse = d = 130 sec∅

As sec ∅ = 1 / cos∅

so d = 130 sec∅    or d = 130 / cos∅

d = 130 / cos(70°)

d =  380 feet

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Answer:

230

Explanation:

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I = Moment of inertia = 6 kgm²

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K=\dfrac{1}{2}I\omega^2\\\Rightarrow K=\dfrac{1}{2}6\times 3600^2\\\Rightarrow K=38880000\ J

Energy used in one acceleration

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Number of accelerations would be given by

n=\dfrac{38880000}{168750}\\\Rightarrow n=230.4

So the number of complete accelerations is 230

8 0
2 years ago
Which of the following represents a convex lens?<br> A. +f<br> B. -di<br> C. -f<br> D. +di
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Choice A
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2 years ago
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A particular string resonates in four loops at a frequency of 320 Hz . Name at least three other (smaller) frequencies at which
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Answer:

160 Hz  ,  240 Hz  , 400 Hz

Explanation:

Given that

Frequency of forth harmonic is 320 Hz.

Lets take fundamental frequency = f₁

f_1=\dfrac{320}{4}\ Hz

f₁=80 Hz

Frequency of first harmonic = f₂

f₂=2 f₁

f₂ =2 x 80 = 160 Hz

Frequency of second harmonic = f₃

f₃= 3 f₁=3 x 80 = 240 Hz

Frequency of fifth harmonic = f₅

f₅=  5 f₁= 5 x 80 = 400 Hz

Three frequencies are as follows

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6 0
2 years ago
A ship 1200m off shore fires a gun. how long after the gun is fired will it be heard on the shore?​
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Answer:

We know that the speed of sound is 343 m/s in air

we are also given the distance of the boat from the shore

From the provided data, we can easily find the time taken by the sound to reach the shore using the second equation of motion

s = ut + 1/2 at²

since the acceleration of sound is 0:

s = ut + 1/2 (0)t²

s = ut    <em>(here, u is the speed of sound , s is the distance travelled and t is the time taken)</em>

Replacing the variables in the equation with the values we know

1200 = 343 * t

t = 1200 / 343

t = 3.5 seconds (approx)

Therefore, the sound of the gun will be heard at the shore, 3.5 seconds after being fired

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2 years ago
Consider a system consisting of an ideal gas confined within a container, one wall of which is a movable piston. Energy can be a
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Answer:

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Explanation:

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8 0
2 years ago
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