Q: 8.17 A rocket is fired vertically with a speed of 5 km s-1 from the earth’s surface. How far from the earth does the rocket go before returning to the earth? Mass of the earth ; mean radius of the earth ; .
The total energy is given by :
Total energy = Potential energy + Kinetic energy
At the highest point velocity will be zero.
Thus the total energy of the rocket is :
Now we will use the conservation of energy :
Total energy initially (at earth's surface) = Total energy at height h
Hence the height achieved by the rocket from earth's centre = R + h
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