Question

list the condition needed for formation shadow

Answer 1

An opaque object , an torch .

To form a shadow we have to put the object and then flash the light . behind the object the shadow would be formed of the opaque object.

Answer 2

A light source. Shadows fall from an illuminated object. The angle and intensity and depends on how much light is striking that object. Harsh, direct light produces sharply defined, deep shadows. A softer light with less focus produces softer and more filled shadows.