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3 years ago

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Which statement about how light travels is true? A Light waves need a medium to travel, and they travel at the same speed even i

f the light source is moving. B Light waves can travel in a vacuum and travel at a constant speed even if the light source is moving. C Light waves can travel in a vacuum and will travel faster if the light source is moving forward. D Light waves need a medium to travel, and they travel faster if the light source is moving forward.

2 answers:

creativ13 [48]3 years ago

8 0

The answer is a B Light wave can travel in a vacuum and travel at a contest speed even if the light source is moving

Pie3 years ago

7 0

Answer:

Light wave can travel in a vacuum and travel at a contest speed even if the light source is moving

Explanation:

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Answer:

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Explanation:

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2 years ago

The circumference of a sphere was measured to be

professor190 [17]

To solve this problem we will apply the concepts related to the calculation of the surface, volume and error through the differentiation of the formulas given for the calculation of these values in a circle. Our values given at the beginning are

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And

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Maximum error:

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$dA = \frac{76}{\pi}cm^2$

The relative error is that between the value of the Area and the maximum error, therefore:

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$V = \frac{4}{3} \pi r^3$

$V = \frac{4}{3} \pi (\frac{38}{\pi})^3$

$V = \frac{219488}{3\pi^2}$

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$\frac{dV}{dr} = \frac{4}{3} 3\pi r^2$

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$dV = 4r^2 (\pi dr)$

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3 0

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vladimir1956 [14]

The resultant vector is 11√2 km due north east.

<h3><u>Explanation:</u></h3>

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Here firstly for the magnitude,

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