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0
votes
0answers
13 views

Can the ratio (direct sunlight intensity)/(indirect sunlight intensity) on a vertical wall be determined?

Consider a vertical wall in any cardinal direction. A flat sunshade (is mounted horizontally on the wall, for example 2 meters above the ground. The sunshade blocks all direct sunlight but since the ...
4
votes
2answers
80 views

Does an object travelling at the speed of light cast a shadow? [closed]

Asked by my 8yo today and left me scratching my head.
1
vote
1answer
50 views

Does this shadow diffraction effect have a name?

I noticed a cool diffraction effect today as I was sitting outside in bright sunshine: Suppose you have a fixed edge casting a shadow. If you put your hand on the side of the edge nearer to the ...
8
votes
1answer
222 views

Why is my shadow deformed and not the shadow of the ceiling? [duplicate]

Look at these two photos of my shadow from sunlight. Case 1: My shadow is separated from the shadow of the ceiling and my head is round. Case 2: But when I walk a little more and the shadow of my ...
4
votes
1answer
47 views

Is single tree shadow locally affecting air temperature?

In other words, is the air temperature under a single tree different from a couple meters away, in a hot day and under the sun? There are several effects potentially interacting: Tree transpiration ...
7
votes
3answers
550 views

What determines the sharpness of a shadow?

What are the factors that affect the sharpness of a shadow? I would think that the distance between the light source and the object, the distance between the object and the shadow, and the size of ...
1
vote
1answer
181 views

why shadows become dark when light intensity increases? [closed]

I observed following phenomena today: in my room with some lightings, there is a stuff toy placed in front of a wall. The ambient lighting doesn't cause any shadow on the wall currently. Scene 1: ...
1
vote
2answers
59 views

Optics of perceived shadows on LCD monitor

After changing my desktop wallpaper on my LED-lit LCD monitor to one with a dark corner, I started seeing shadows on where the clock widget is while looking sideways at the screen. These shadows move ...
1
vote
1answer
57 views

Image formation or Diffraction?

I was watching this video on the YouTube channel Veritasium. In this episode, the host shows people paper containing holes of different shapes in the middle. So there is a paper which has a hole in ...
5
votes
1answer
959 views

Why is the shadow of a wind turbine a bit slow at first then very quickly, etc. and not equivalent to the wings?

When I stand at a wind turbine and look at the shadow on the ground, the shadow is a bit slow at first then very quickly, etc. Very strange.
0
votes
4answers
55 views

Can the term «shadow» pertain to anything else than light? [closed]

Can the term shadow pertain to anything else than light? Feel free to interpret this question in the widest sense possible.
4
votes
2answers
423 views

A light so strong it has a shadow

I have recently taken an interest in shadows. I know that in order for a shadow to exist that you must have a solid in the way of the light. My hypothesis is that there can be a light so strong, like ...
29
votes
6answers
8k views

Can you run away from your shadow?

Now this might be a silly question but it's actually bugging me, this one might be easier to understand if you have kids that watch (or used to watch) Peppa Pig. In one of the episodes, about shadows, ...
26
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5answers
7k views

Can the sun cast a shadow?

The sun's light can cast the shadow of another object, but does it ever cast its own shadow?
-7
votes
2answers
654 views

Are shadows underwater “wet”? [closed]

Sorry if this is the wrong place to post this but it seemed the most appropriate. I read a riddle earlier today that mentioned something about shadows underwater and it got me thinking.. Would a ...
4
votes
3answers
308 views

Why does the point of intersection of two shadows look brighter?

When I sit in my garden during the day I always keep looking at the two intersecting shadows of two rods. It looks something like this: What I find weird about it is that at the point of ...
125
votes
6answers
13k views

Why do shadows from the sun join each other when near enough?

I was laying on my bed, reading a book when the sun shone through the windows on my left. I happened to look at the wall on my right and noticed this very strange effect. The shadow of my elbow, when ...
4
votes
4answers
719 views

Why do the passing objects' shadows run in the direction of the moving train?

While travelling in the train on the sunset, I have noticed the strange phenomenon. The shadows of the lonely trees and lampposts, that stay along the railroad, are moving on the wall in the same ...