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3 years ago

Explain why the intensity of the light in a flashlight beam decreases as the flashlight moves farther away.

Physics

1 answer:

Karolina [17]3 years ago

7 0

Ir=Initial Intensity/Area of spread=Io4πr2
Ir∝1r2

It is seen from this expression that intensity is inversely proportional to the square of the distance. As we move away from the light source the intensity decreases at the rate of square of the distance from the source.

Brightness being the perception of intensity. more the intensity more bright the object is perceived and vice versa.

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Ann [662]

Answer:

The answer is 'D' none

Explanation:

In the figure shown we have

$2Tsin(\theta )=mg\\\\\therefore T=\frac{mg}{2sin(\theta )}$

From the figure we can see that

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3 years ago

Select all that apply. Greenhouse gases _____. absorb solar energy absorb carbon dioxide release carbon dioxide are released dur

MariettaO [177]

Possible answers are:
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7 0

3 years ago

Read 2 more answers

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Schach [20]

Answer:

Explanation:

Appears to be the vertexes of a triangle.

AB = √(-6 - (-2))² + (3 - 4)²) = √17

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BC = √(-2 - (-8))² + (4 - 3)²) = √37

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3 years ago

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maria [59]

Answer:

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Explanation:

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Answer:

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