Orbital motionEdexcel A-Level Physics: Mind map

Exam questions on Orbital motion

1. An Earth-observation satellite moves in a circular orbit at a height of 600 km above the surface of the Earth. The mass of the Earth is 5.97×10²⁴ kg, its radius is 6.37×10⁶ m and the gravitational constant is G = 6.67×10⁻¹¹ N m² kg⁻².
   Calculate the orbital speed of the satellite.2 marks
2. A television company uses a communications satellite that is placed in a geostationary orbit above the Earth. The mass of the Earth is 5.97×10²⁴ kg, its radius is 6.37×10⁶ m and the gravitational constant is G = 6.67×10⁻¹¹ N m² kg⁻². One day is 8.64×10⁴ s.
   Calculate the orbital radius of the satellite.2 marks
3. The Moon orbits the Earth in an approximately circular path of radius 3.84×10⁸ m. Its orbital period is 27.3 days. Take G = 6.67×10⁻¹¹ N m² kg⁻².
   Use the motion of the Moon to calculate the mass of the Earth.3 marks