Chapter Name: Reflection of Light By Different Surfaces
Activity Name: Verification of laws of reflection in Reflection of Light By Different Surfaces
This experiment aims to verify the laws of reflection of light, specifically the angle of incidence being equal to the angle of reflection.
- Mirror strip, drawing board, white paper, pins, clamps, scale, and pencil.
Step by Step Procedure:
- Fix a white paper on the drawing board using clamps.
- Draw a straight line AB at the center of the paper and a normal (ON) to AB at point ‘O’.
- Draw a straight line PQ at a certain angle (angle i) with respect to ON.
- Place two pins vertically at points P and Q on the paper.
- Observe the images PI and QI of the pins P and Q, respectively, in the mirror kept along line AB.
- Place two more pins R and S such that they are in the same line as PI and QI.
- Join pins R, S, and point O to complete the setup (Figure 7).
- Measure the angle between RS and ON (angle of reflection).
- Observe that the angle of incidence (angle i) is equal to the angle of reflection (angle r).
- Repeat the experiment for different angles of incidence and measure the corresponding angles of reflection.
- The experiment will demonstrate that the angle of incidence is equal to the angle of reflection for various incident angles.
- Ensure the mirror strip is clean and free from any dust or smudges.
- Keep the pins and mirror perpendicular to the paper to avoid errors in measurement.
- Use a protractor or suitable measuring instrument to measure the angles accurately.
Lesson Learnt from Experiment:
This experiment confirms the laws of reflection, which state that the angle of incidence is always equal to the angle of reflection when light reflects off a surface.