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3 years ago

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PLEASE HELP! Daniel is 50.0 meters away from a building. He observes that his line-of-sight to the tip of the building makes an

angle of 63.0° with the
horizontal. What is the height of the building?
A. 174 m
B. 110 m
C. 98 m
D. 50 m

1 answer:

zavuch27 [327]3 years ago

5 0

Answer:

The height of building should be 98.13 m plus the height of Daniel. Since the 63° was measured from his eye level.

Explanation:

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Answer:

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Explanation:

The force that both satellites experience is:

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where

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$\theta=30^{\circ}$ is the angle between the direction of the force and the displacement of the sled

Substituting numbers into the formula, we find

$W=(25.0 N)(3.20 m)(cos 30^{\circ})=69.3 J$

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According to the work-energy theorem, the work done by the applied force is equal to the change in kinetic energy of the sled:

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We therefore know that the change in kinetic energy of the sled is equal to this value:

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The change in kinetic energy of the sled can be rewritten as:

$\Delta K=K_f - K_i = \frac{1}{2}mv^2-\frac{1}{2}mu^2$ (1)

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We can calculate the variation of kinetic energy of the sled, $\Delta K$ , after it has travelled for d=3 m. Using the work-energy theorem again, we find

$\Delta K= W = Fd cos \theta =(25.0 N)(3.0 m)(cos 30^{\circ})=65.0 J$

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Answer:

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Explanation:

The motion of the ball is a free fall motion, so we can use the suvat equation:

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As the question is about changing in frequency of a wave for an observer who is moving relative to the wave source, the concept that should come to our minds is "Doppler's effect."

Now the general formula of the Doppler's effect is:
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S_A_V [24]

Can you please fill in whatever goes in the blanks ?

Without them, the question makes no sense and has no answer.

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