Unit 5: Shadows

Light travelling in straight lines, materials and shadows, shadow size and length, measuring light, and the scientists who studied light.

• 5.1 Light travels in straight lines – Light cannot bend round corners.
• 5.2 Which materials let light through? – Transparent, translucent or opaque?
• 5.3 Silhouettes and shadow puppets – Dark shapes against the light tell stories.
• 5.4 What affects the size of a shadow? – Move the object, move the light – and watch the shadow change.
• 5.5 Investigating shadow lengths – Shadows change length as the Sun moves across the sky.
• 5.6 Measuring light intensity – How bright is bright? Measure it in lux.
• 5.7 How scientists measured and understood light – Ibn al-Haytham, Newton and Rømer – a thousand years of discoveries.