Hohmann Transfer Problems

Since several people had difficulties with these questions, here is a step-by-step approach to such problems.

(1) Draw a diagram - and add in the basic parameters - those you know and those you want.

(2) Get the correct M - what is being orbited?

(3) Which is r1 and which is r2?

(4) What exactly is the quantity that is being asked for?

(5) Does the answer make sense? For transfers on solar orbits (interplanetary transfers) the deltaV~ km/s. For transfers orbiting planets the deltaV~ m/s to 100s m/s.

(6) The process works in reverse - then deltaV_outer is to speed up and deltaV_inner is to slow down.