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3 years ago

15

Ab observer detects an apparent change in the frequency of sound waves produced by an airplane passing overhead. This phenomenon

illustrates
A. the doppler effect
B wave amplitude increase
C the refraction of sound waves
D Wave intensity increase

1 answer:

ss7ja [257]3 years ago

8 0

Hello There

Answer: The Doppler effect

Reason: The Doppler effect is an increase or decrease in the frequency of sound, light, or waves as the source and observer move to each other. An example would be a firetruck with its siren on driving away from you.

I hope this helps
-Chris

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Assume that a satellite orbits mars 150km above its surface. Given that the mass of mars is 6.485 X 10^23kg, and the radius of m

Kisachek [45]

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3 years ago

A man climbs a wall that has a height of 8.4 meters and gave the potential energy of 4620 joules. His mass is about_____ kilogra

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Gravitational potential energy = mass x acceleration due to gravity x height
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3 years ago

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As we know that in transformers we have

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here we know that

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$N_s = 50 coils$

$N_p = 300 coils$

now from above equation we will have

$\frac{V}{120} = \frac{50}{300}$

$V = 20 Volts$

now we have to reduce this voltage to final voltage of V = 4 V

so again we will have

$\frac{V_s}{V_p} = \frac{N_s}{N_p}$

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3 years ago

Read 2 more answers

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5 0

4 years ago

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Ludmilka [50]

Answer:

62.1 ft

Explanation:

We know that $1 gpm= 0.0022 ft^{3}/s$ hence 240 gpm will be

$240*0.0022=0.528 ft^{3}/s$

From the formula of obtaining efficiency

$\eta=\frac {\gamma Q h_a}{500W_{in}}$ and making $h_a$ the subject we have

$h_a=\frac {\eta*550*W_{in}}{\gamma Q}$ where Q is flow rate, $\gamma$ is specific weight of water, $h_a$ is actual head rise and $W_{in}$ is the power input to the compressor

Substituting 0.62 for $\eta$ , 6hp for $W_{in}$ , $62.4 lb/ft^{3}$ for $\gamma$ and $0.528 ft^{3}/s$ for Q then

$h_a=\frac {0.62*550*6}{62.4*0.528}=\frac {2046}{32.9472}=62.09936\approx 62.1 ft$

Therefore, actual head rise of the water being pumped is 62.1 ft

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3 years ago