What is a shadow

When light passes through opaque object, some of it would be blocked and form a shaedow.The shadow is formed according to the shape of the object as light moves in straight line.
When light source is blocked by an opaque /translucent object a black spot is formed on the opposite side of the light source ...that black spot is called shadow.
CHARACTERISTICS OF SHADOWS
🌻black in colour .
🌻outline of structure of the object.
🌻size depends upon the light source and the object.
🌻always forms on the opposite side of the light source .
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