How do we know that light travels in a straight line? - Presentation

The concept that light travels in straight lines is a fundamental principle in the study of optics. To explore this idea, pupils are encouraged to engage with a series of activities and experiments. Initially, they are directed to an online resource that demonstrates the straight-line path of light through practical examples. In one such experiment, three cards with holes are aligned; when the holes do not line up, the light cannot pass through, but once they are arranged in a straight line, the light travels through all three cards without obstruction. This simple yet effective demonstration reinforces the concept that light's path is linear.

Further experimentation involves observing how light behaves when it encounters an irregular, shiny surface. Even though the light scatters and reflects in various directions, it is still fundamentally traveling in straight lines before it hits the surface. Pupils are then tasked with setting up their own experiments to illustrate the reflection of light in straight lines, using the materials and guidance provided. The activities are structured to encourage metacognitive learning, prompting students to plan, conduct, and evaluate their experiments critically. This process not only deepens their understanding of how light travels but also enhances their skills as inquisitive scientists, capable of reflecting on their methodologies and learning from their investigations.