Answer:
The final velocity will be half of the initial velocity of the spacecraft.
Step-by-step explanation:
Angular momentum is conserved for the circular force motion and central force motion.
Considering
L = MVR = Constant
Where
M = Mass of the object
V = Velocity of the object
r = radius of circle
We know that
V =
So,
=
As per the given data
= Initial Radius = 300 km
= Final Radius = 600 km
= Initial Velocity =
= Final Velocity =
Placing values in the formula
=
=
=
Hence, The final velocity will half of the initial velocity of the spacecraft.