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What belongs in each mystery box?

Every mystery box holds the same value. Make the two sides balance.

4 × ? + 545Equal values make a level balance.

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ScienceAges 13-15Physics (O Level): Space physics
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Orbital speed of planets & satellites

A satellite orbits in a circular path of radius r = 12000 km with an orbital period of T = 20 hours. Using v = 2πr ÷ T with π = 3.14, calculate its orbital speed in km/h.

Use the O Level Space Physics orbital speed equation v = 2πr ÷ T to calculate the speed of an orbiting satellite or planet.

Orbit Radius r = 12000 km · T = 20 h · Orbital Speed: v = 2πr ÷ T
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