Solar Crookes Radiometer Key benefits Clear visual demonstration of energy to motion: Shows how light and heat cause movement, making abstract physics concepts easy to understand and explain. Dual purpose: Functions as both an educational science toy and an attractive desktop ornament that draws attention without requiring batteries or wiring. Durable, construction: Made from boron glass for sturdy use and long service life. Features Operates under sunlight or strong artificial irradiation; the four internal vanes rotate automatically when exposed to sufficient light. Working principle: The black vane surfaces absorb heat while the white vane surfaces release heat, producing the temperature differences that drive rotation. Material: boron glass for improved toughness and resistance to cracking. Size: Height 21 cm 8.27 inch; Ball diameter 9 cm 3.54 inch; Base diameter 8 cm 3.15 inch. Package includes: 1 Solar Crookes Radiometer. Measurement note: Please allow slight dimensional variation of 1 to 2 cm due to manual measurement. How this product helps Makes physics lessons tangible by turning light energy into visible motion, supporting classroom demonstrations and hands on learning. Enhances a workspace or living area with subtle, scientifically driven motion that sparks curiosity and conversation. Provides a safe, low maintenance science display that requires only light to operate. Practical use scenarios Classroom demonstration: Use during lessons on radiation, heat transfer, and molecular motion to give students a direct visual example of energy conversion. Office or home desk display: Place on a desk, shelf, or mantelpiece where sunlight or a bright lamp can activate the vanes, adding an engaging decorative element to the space. Gift or learning activity: A thoughtful gift for students, hobbyists, and friends for birthdays, holidays, housewarmings, or science fairs. Suitable locations Desk, table, shelf, cabinet, entrance, fireplace, office, bedroom, living room. This solar Crookes radiometer combines simple operation, instructional value, and attractive glass construction to provide a reliable demonstration piece and decorative item.