PHYSICS LESSON PLAN

ICSE Class 6 Physics Lesson Plan

Rectilinear propagation of light
Pinhole camera – principle and working
Shadow formation – by point source and extended sources
Rays and beams of light – ray, parallel beam, convergent beam, divergent beam
Formation of shadows:
- By a point source
- By an extended source smaller than the object
- By an extended source larger than the object

Understand that light travels in a straight line (rectilinear propagation).
Explain the working principle of a pinhole camera.
Differentiate between types of light beams – parallel, convergent, and divergent.
Learn to draw ray diagrams showing shadow formation under different conditions.
Identify umbra and penumbra formed by different light sources.

Begin with a discussion: ask students what happens when light passes through small holes or gaps.
Demonstratation of rectilinear propagation of light using a straight tube or three cardboard pieces with small holes aligned in a straight line. When light passes through all three holes, it shows that light travels in a straight line.
Introduce the concept of a pinhole camera and explain its working with a diagram — formation of an inverted image of an object on the screen.
Explain the concept of a ray and beam of light:
- Single ray – a thin line showing direction of light.
- Parallel beam – rays parallel to each other (e.g., sunlight).
- Convergent beam – rays meeting at a point.
- Divergent beam – rays spreading out from a point source.
Discuss shadow formation by:
- Point source – sharp, dark shadow (umbra).
- Extended source smaller than object – clear umbra and small penumbra.
- Extended source larger than object – umbra and broad penumbra.
Demonstration of pinhole camera and shadow formation using simple models and lighter .

Activity 1: Demonstration of Rectilinear Propagation of Light -Align of three cardboard pieces with pinholes and shines light through them.

Students observe that light passes through only when holes are in a straight line.
This verifies that light travels in a straight line.

Activity 2: Demonstration of a Pinhole Camera

Use of a simple pinhole camera made from a cardboard box.
Students observe the inverted image of an object on the opposite side.
Explanation of how image size depends on the distance of the object and the hole.