This resource, from the Royal Observatory Greenwich, has a video that introduces 'light' as the electromagnetic spectrum and how an electromagnetic wave is made. It discusses the wavelength, speed and frequency of electromagnetic waves and how we can detect them. How light interacts with matter and the concept of...

This resource, from the Royal Observatory Greenwich, introduces students to how our understanding of gravity has changed over time, and what this means for the gravitational field strength of different bodies in our galaxy.

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