A sapceship nears the Moon along a parabolic trajectory that almost toches the Moon's surface. In order to transfer closest approach. The engine ejects gas ata speed of `u = 4 km//s` realtive to the spaceship In its direction of motion. If `v_(1) =` velocity of spaceship in parabolic trajectory, when it almost touches the earth and `v_(2) =` velocity of spaceship in circular orbit when it almost to'uches the earth. Then what friction of total mass should the fuel burn to transfer space ship to circular orbit?

Answer

`M = M_(0)e^((v_(1)-v_(2))/(u)) ; T = 3600 K`