Question

what is the reason of if the height of the orbit of a satellite increases its velocity must also increase?

Answer 1

r1 < r2
(r1 and r2 are two different heights of the orbit of a satellite)
[ w = v/r]
where 'w' is angular velocity and 'v' is tangential velocity , and 'r' is the height of the orbit
now by (1)
H1<H2
multiplying both by 'w'
wr1<wr2
V1<V2
that means final velocity is greater that initial velocity
hence
velocity increased on increasing the height of the orbit