Wait, it is not why. It's how. Shadows are formed because light travels in a straight line. Try to understand it yourself.
second answer: when something come in the way of light it, light is not able to travel anymore. and the areas where is no light, it is dark and we call this dark area as shadow
A shadow is formed when light is blocked by an object.
the angle at which a shadow is formed
longest
an angle (that can be on the earth) at which an angle could be formed by the sun.
Grease paper is translucent. It let's a bit of light through but not all. Card board is opaque. It lets no light through. Therefore, the shadow cast by cardboard will be darker and more defined whereas the grease paper lets light through, making the shadow lighter and less focused.
A shadow is formed when light is blocked by an object.
when a shadow is formed there should be an opaque object the picture can be formed on the screen.
the angle at which a shadow is formed
shadow
A normal shadow.
shadow
at noon the shadow is point sized {smaller} and in morning and evening the shadow is the longest.
The shadow formed would be tetrahedrons with an nostalgic way of cooperating with the society at that time.
In total darkness.
because the tree is blocking the light source so it forms a shadow.
Light,
Shadow