The answer to "I am as big as you but don't weigh anything" should be mirror image, or reflection. A shadow can have many different sizes, depending on how far away and at what angle the light source is. So it being "as big as you" would be in most cases incorrect.
The answer to "I am as big as you but don't weigh anything" should be mirror image, or reflection. A shadow can have many different sizes, depending on how far away and at what angle the light source is. So it being "as big as you" would be in most cases incorrect.