Orbits and Satellites: Why the Space Station Never Lands, Closer = Faster | GCSE Physics

Orbits for GCSE Physics, animated, starting with a surprise: the space station is falling all the time, it just keeps missing the Earth. Newton's cannon shows why: fire fast enough and the ground curves away as quickly as the ball falls, so gravity provides the force for every orbit. Planets, moons and artificial satellites compared, and comets on stretched ellipses that whip round fastest near the Sun (Edexcel). Then the Higher tier ideas (AQA and OCR; all tiers on Edexcel): in a circular orbit the speed is constant but the velocity keeps changing, so the satellite is accelerating towards the centre; and for a stable orbit, a smaller radius means a higher speed (Mercury about 47 km/s, Earth 30, Neptune 5; the space station 7.7 km/s, a geostationary satellite 3.1 km/s). Why drag lowers an orbit, geostationary and polar orbits (named by OCR), and weight on other worlds with W = mg (Edexcel): a 70 kg astronaut weighs 700 N on Earth and 112 N on the Moon, and a probe that weighs 1500 N on Earth weighs 555 N on Mars. Finished with an exam-style 'explain why it is accelerating' answer, point by point, and three mistakes that cost marks. Covers: AQA 4.8.1.3 · Edexcel 7.1P, 7.5P, 7.6P, 7.7P · OCR Gateway P8.3e–g (separate Physics only; speed, velocity and orbit radius are Higher tier on AQA and OCR, all tiers on Edexcel). 0:00 Intro 0:08 Hook 0:34 Falling and missing 1:11 What orbits what 1:33 Comets 1:54 Constant speed, changing velocity 2:40 Closer is faster 3:27 Change the speed, change the orbit 3:47 Geostationary and polar orbits 4:29 Weight on other worlds 5:08 A probe on Mars 5:47 Exam-style question 6:14 Common mistakes 6:40 Summary Narrated with an AI voice. Worked Example is not affiliated with or endorsed by AQA, OCR or Pearson Edexcel. Exam board names are used only to show which specifications a video covers.