Multiple Choice
Gravitational potential energy: Sputnik I was launched into orbit around Earth in 1957. It had a perigee (the closest approach to Earth, measured from Earth's center) of 6.81 × 106 m and an apogee (the furthest point from Earth's center) of 7.53 × 106 m. What was its speed when it was at its perigee? The mass of Earth is 5.97 × 1024 kg and G = 6.67 × 10-11 N ∙ m2/kg2.
A) 7180 m/s
B) 7840 m/s
C) 8230 m/s
D) 11,000 m/s
E) 13,400 m/s
Correct Answer:

Verified
Correct Answer:
Verified
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