# The Velocity of a Rocket at Parigee of an Elleptic Orbit

Problem # 4 - The rocket is traveling in a free-flight elliptical orbit about the earth such that e = 0.76 and Its perigee is 9Mm as shown. Determine its speed when it is at point B. Also determine the sudden decrease in speed the rocket must experience at A in order to travel in a Circular orbit about the earth.

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Problem # 4 - The rocket is travelling in a free-flight elliptical orbit about the earth such that e = 0.76 and Its perigee is 9Mm as shown. Determine its speed when it is at point B. Also determine the sudden decrease in speed the rocket must experience at A in order to travel in a Circular orbit about the earth.

The perigee distance of an ellipse is given by

r1 = a*(1 - e)

Where a is the semi-major axis of the ellipse and the apogee distance is given ...

#### Solution Summary

The solution is using the laws of gravitational attraction, conservation of angular momentum and conservation of energy to calculate the speed of rocket at perigee. Also the change in velocity to convert the orbit in circular one.