Question

you can make a shadow puppet of a dogs head using your hand and a light source. explain in the photo, why does the shadow of a dogs head form on the wall behind the hand?

Explanation:

Light travels in straight lines. When light from the source hits the hand, the hand blocks the light. The area behind the hand where light cannot reach forms a shadow. The shape of the shadow (like a dog's head) depends on the shape of the hand's position as it blocks the light.

Answer:

Light travels in straight lines. The hand blocks light, creating a shadow (dog - head - shaped due to hand’s position) on the wall.