Page 2 - Lesson Note- Reflection Of Light

History of reflection of light: -

Ancient Beginnings

• Around 3000 BCE:
The first mirrors were made of polished stones like obsidian (volcanic glass)
by ancient civilizations such as the Egyptians and Mesopotamians.

Greek Contributions
• Euclid (circa 300 BCE):
One of the first to systematically study the geometry of light. He stated that
light travels in straight lines and described the laws of reflection
mathematically.

Renaissance and Beyond

• Isaac Newton (17th century):
Studied the nature of light and used mirrors in his reflecting telescope
design.

Modern Era

• Today, the laws of reflection are a basic part of physics and used in
countless applications—from mirrors and periscopes to fiber optics and
laser technologies.

Activities

1. Periscope Making

Objective: To demonstrate reflection of light using mirrors.
Materials: Two small mirrors, a cardboard box, tape, and
scissors.
Process:-

• Cut two holes in the box—top and bottom.
• Place the mirrors at 45° angles inside facing each
other.
• Look through the bottom and observe objects from a
higher level.
2. Shadow Play

Objective: To understand how shadows form and change.
Materials: Torch or sunlight, opaque object (toy), white
screen or wall.
Process:-

• Place the object between the light and the wall.
• Move the object closer/farther from the screen.
• Observe changes in shadow size and sharpness.