GPS is accurate to 30cm. Here's how. #shorts

Your phone knows where you are to within 30 centimetres — using satellites 20,000 km away, atomic clocks, and Einstein's relativity. Here's the engineering behind it.

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GPS works by measuring the time it takes for signals from satellites to reach your phone. Because light travels at a fixed speed, your phone can calculate the exact distance to each satellite. With signals from 4 satellites, it pinpoints your location to a single point in space.

But 30cm accuracy requires timing precise to 20 nanoseconds. That's why each GPS satellite carries an atomic clock — one that measures caesium atoms oscillating 9,192,631,770 times per second, and loses just 1 second every 300 million years.

And there's one more layer. Time moves slightly faster in orbit than on the ground (Einstein's General Relativity). Without correcting for this every second, your GPS would drift by 10 kilometres per day.

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Topics covered in this Short:
→ How GPS trilateration works
→ Why 4 satellites are needed (not 3)
→ Caesium atomic clocks explained
→ Einstein's relativity correction in GPS
→ How GPS achieves 30cm accuracy

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#gps #HowItWorks #science #engineering #physics #space #satellites #atomicclocks #einstein #Phenomica #shorts #technology #scienceshorts #STEM #explained

Видео GPS is accurate to 30cm. Here's how. #shorts канала Phenomica