Engineering Board Exam Reviewer · Physics · hard
What is the escape velocity from the Earth's surface? (g = 9.81 m/s2, R = 6371 km)
- 11.18 km/s
- 7.91 km/s
- 125.00 km/s
- 5.59 km/s
Answer
A. 11.18 km/s
Solution
ve = sqrt(2gR) = 2 × 9.81 × 6.371 × 106 = 11180 m/s = 11.18 km/s. (Orbital speed near the surface is sqrt(gR) 7.9 km/s.)
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