If light falls on anything on earth, a shadow is formed. In the language of science, shadow is formed by everything present on the earth which has mass i.e. which is opaque. The shadow of an object is also formed according to its size, that is, the shadow of a small object is small and that of a big object is big. However, by changing the angle of the light you can also make the shadow larger than the object.
airplane shadow
You must have noticed that whenever a plane flies in the sky during the day, its shadow is not formed on the earth. In such a situation, the question arises that the plane also has mass and while flying in the sky, sunlight falls on it too, then why is it that its shadow is not formed on the earth?
When an airplane is on the ground, you can easily see its shadow. But this does not happen after flying in the sky. Experts blame diffraction of light for this. Understand it like this, when light travels in a straight line and hits a sharp edge, then the rays of light bend slightly from the edges and this bending of light is called ‘diffraction of light’.
Even the shadow of the kite is not visible
It is not that only the shadow of the airplane is not visible. When a kite flies very high in the sky, we cannot see its shadow on the ground. Diffraction of light is responsible for this also. However, when your kite is below a certain height, you can easily see its shadow on the ground. But the size of this shadow depends on the size of the kite and the angle of light.
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