Concept of light and Shadow

Shadows change due to the change in relative positions of source of light and object.

Concept of gram atom, Concept of gram mole and Concept of gram equivalent

What is a shadow?

What are shadows ?

A point source of light is hung 30 feet directly above a straight horizontal path on which a man of 6 feet in height is walking.How fast is the man's shadow lengthening and how fast the tip of shadow is moving when he is walking away from the light at the rate of 100 ft/min.

Does the concept of photon energy shed any light (no punintended)on the question of why X rays are so much more penetrating than visible light? Explain.

A source of light is hung h mts.,directly above a straight horizontal path on which a boy'a mts.in height is walking.If a boy walks at a rate of b mts/sec.from the light then the rate at which his shadow increases