$A$ satellite of mass $m$,revolving around the Earth of radius $r$,has kinetic energy $E$. Its angular momentum is:

Initially, a satellite of $100 \ kg$ is in a circular orbit of radius $1.5 R_E$. This satellite can be moved to a circular orbit of radius $3 R_E$ by supplying $\alpha \times 10^6 \ J$ of energy. The value of $\alpha$ is . . . . . . .
(Take Radius of Earth $R_E = 6 \times 10^6 \ m$ and $g = 10 \ m/s^2$)

$A$ satellite is orbiting the Earth. If its orbital radius is reduced to half of its initial value,then the percentage change in its total energy is: (in $\%$)

$A$ skylab of mass $m \ kg$ is first launched from the surface of the earth into a circular orbit of radius $2R$ (from the centre of the earth) and then it is shifted from this circular orbit to another circular orbit of radius $3R$. The minimum energy required to shift the lab from the first orbit to the second orbit is:

Binding energy of a revolving satellite at height $h$ is $3.5 \times 10^8 \ J$. Its potential energy is

For a satellite moving in an orbit around the earth,the ratio of kinetic energy to potential energy is