Understanding the Effects of Distance on Light Intensity

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In summary, when you shoot or flash lights up to the sky, they will continue to travel until they are either absorbed or too weak to detect. Clouds can scatter the light, and the universe does not have a top. When flashing a light onto a distant wall, the light will appear weaker or even disappear because it has spread out, while it will appear stronger when the wall is closer. The strength of the light is determined by the amount of light that falls on a given area on the wall.
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terryds
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If I shot/flash lights up to the sky, will the lights or photons fly up to the sky then to the space then to the top of the universe?? Will it stop?
 
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terryds said:
If I shot/flash lights up to the sky, will the lights or photons fly up to the sky then to the space then to the top of the universe?? Will it stop?
The light will travel until one of two things happens to it: Either it will be absorbed because space is not completely empty, or it will spread out until it becomes too weak to detect. That's assuming that it makes it past the atmosphere of the earth, which it won't on a cloudy day.
 
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And the effect of the clouds is to scatter the light.
 
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And the universe doesn't have a top.
 
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Nugatory said:
The light will travel until one of two things happens to it: Either it will be absorbed because space is not completely empty, or it will spread out until it becomes too weak to detect. That's assuming that it makes it past the atmosphere of the earth, which it won't on a cloudy day.

pixel said:
And the effect of the clouds is to scatter the light.

Vanadium 50 said:
And the universe doesn't have a top.

Thanks for your answers.
One more question..
If I flash the light onto the wall which is far from myself, why does the light become weak or even disappear?? But, if the wall is near, why does the light become strong?
What absorbs the light in its travel to the wall?
 
  • #6
terryds said:
Thanks for your answers.
One more question..
If I flash the light onto the wall which is far from myself, why does the light become weak or even disappear?? But, if the wall is near, why does the light become strong?
What absorbs the light in its travel to the wall?

as nurgatory said in as earlier answer, it spreads out
like this ...

inverse_square_law.jpg

Dave
 
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  • #7
terryds said:
If I flash the light onto the wall which is far from myself, why does the light become weak or even disappear?? But, if the wall is near, why does the light become strong?

What determines how "strong" the light is, to use your term, is how much light falls on a given area on the wall. As davenn showed, the further you put the wall, the more the light has spread so the amount of light per unit area is less compared to when the wall is closer, so it doesn't look as strong.
 
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What causes light to shoot up to the sky?

Light shooting up to the sky can be caused by a variety of factors such as the reflection of sunlight off of clouds or particles in the atmosphere, artificial light sources like fireworks or spotlights, or natural phenomena like the Northern Lights.

Is light shooting up to the sky harmful?

In most cases, light shooting up to the sky is not harmful. However, excessive artificial light pollution can have negative effects on wildlife and disrupt natural ecosystems. It can also contribute to skyglow and reduce our ability to see stars in the night sky.

Can light shooting up to the sky be a sign of a weather phenomenon?

Yes, light shooting up to the sky can sometimes be a sign of a weather phenomenon. For example, light pillars, which are vertical columns of light, can be caused by the reflection of light off of ice crystals in the atmosphere and are often seen in cold, clear conditions.

How does light shooting up to the sky affect the atmosphere?

Light shooting up to the sky can have a minor impact on the atmosphere, as it contributes to light pollution and can disrupt natural rhythms of plants and animals. However, its effects are generally localized and do not significantly impact the overall health of the Earth's atmosphere.

Can light shooting up to the sky be observed from space?

Yes, light shooting up to the sky can be observed from space. Satellites and astronauts have captured images of various light phenomena, such as city lights at night, auroras, and lightning, from their vantage point in space.

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