In Fig. $13-21,$ two satellites, A and $B,$ both of mass $m=270kg,$ move in the same circular

orbit of radius $r=7\mathrm{.}87{10}^{6}m$ around Earth but in opposite senses of rotation and therefore

on a collision course. $($a$)$ Find the total mechanical energy $E_A+E_B$ of the two satellites $+$

Earth system before the collision. $($b$)$ If the collision is completely inelastic so that the

wreckage remains as one piece of tangled material $($mass $=2m),$ find the total mechanical

energy immediately after the collision. $($c$)$ Just after the collision, is the wreckage falling

directly toward Earth's center or orbiting around Earth?

Figure $13-21$ Problem $1.$