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On Kepler-20b, how much fuels is need to launch a rocket to orbit?
... relative to Earth, for the same payload. Assume that Kepler-20b has a radius of 1.87 Earth, and a mass of 9.7 Earth.
2 個解答
- 3 年前最愛解答
Gravity on Kepler-20b is going to be about 2.77 times as strong as it is on Earth's surface, so you'd need about 2.77^2 or 7.68 times the same amount of fuel as it would take to launch the same payload to orbit.
F = G(m1)(m2)/r^2; the only things changing are m1 and r, so 9.7 / (1.87^2) = 2.77 times as much gravitational pull at the surface.
- MorningfoxLv 73 年前
A conventional chemical fueled rocket can be analyzed by the rocket equation. Delta V = V_ex ln( m0 / mf)
V_ex = exhaust velocity
m0 = initial total mass with fuel
mf = final total mass
On Kepler-20b, the rocket needs 104 times as much fuel.
