Question

Can you think of creating a shape that would give a circular shadow if held in one way and a rectangular shadow if held in another way?

Answer 1

When a cylinder is held in sunlight, then a circular shadow or a rectangular shadow can be obtained depending on its orientation related to the Sun.

When the top of the cylinder faces the Sun, then the shadow formed is circular. On the other hand, when the side of the cylinder faces the Sun, then the shadow formed is rectangular.