{Student Work}

 Experiment: Illuminance and the Inverse Square Law 

Grade 11

Objective

To investigate the relationship between illuminance (E) and distance (d) from a point light source, and to verify the inverse square law.

Methodology

Apparatus: Two smartphones were used. One served as a light source (flashlight switched on), while the other acted as a light meter through a lux-measuring application, a made up diffuser, and a ruler.

Procedure:

• 1. The flashlight phone was fixed in place to act as the point source.
     
     

  2. The measuring phone was positioned at varying distances (e.g., 10 cm, 20 cm, 30 cm, etc.) from the source.
     
     

  3. At each distance, students recorded the illuminance in lux as displayed by the app.
     
     

  4. Data was collected, tabulated, and then plotted as Illuminance vs. Distance using GeoGebra.

Results

1-The plotted graph showed that illuminance decreases rapidly with increasing distance.

2-Students concluded that the intensity of light falls off proportionally to the square of the distance from the source, consistent with the theoretical model.

Pedagogical Framework and Strategy

This experiment was designed within an inquiry-based learning framework, where students actively constructed knowledge through direct measurement, analysis, and interpretation.

• Exploration: Students used accessible tools (phones + apps) to simulate professional lab equipment.
  
  

• Collaboration: Data collection was shared among group members, encouraging peer discussion.
  
  

• Integration of Technology: GeoGebra was used for graph plotting and trend analysis, reinforcing mathematical connections to physics.
  
  

• Conceptual Understanding: Rather than passively receiving the inverse square law, students discovered it through evidence, leading to deeper retention.
  
  

Reflection

This activity highlights how everyday technology can be leveraged to deliver hands-on experimental physics even in resource-limited settings. Students demonstrated not only the law of illuminance but also important scientific skills: data recording, graphing, identifying trends, and drawing evidence-based conclusions.

 Review stations: Characteristics of light  

Grade 11

Grade 11 – Physics (Characteristics of Light)

Today I conducted a review activity in the form of learning stations. Students rotated between three stations, each focusing on a different aspect of the section. Each student spent 15 minutes per station before rotating when time was called. By the end of the period, every student had visited and participated in all three stations. 

Student Investigation: Parachute Design and Motion 

Grade 9