Recent content by treebrains

I answered it by understanding that when GPE changes, so does KE (energy is conserved blah blah) 1) And in the first half of the journey (so to speak, really meaning, "as far as the spaceflight is under the influence of Earth's grav field primarily") - GPE is increasing as it recedes from...

It's probably better to do past paper questions that are relevant to changes in GPE. Maybe it might help to understand that everything possesses mechanical energy, which is the sum of KE and GPE. This is how energy is conserved -> GPE is just energy that will turn into KE at some other point in...

slightly off topic... is it valid to also calculate work done using change in KE, given you know the linear orbital velocity?

Because gravitational force only acts downward (i.e. perpendicular to surface of Earth) then it is only a factor to be considered in vertical motion. i.e.: (v)y = (u)y + a(t) -> you know (if on Earth) a=-9.8 of course, so (v)y = (u)y - 9.8(t) automatically. It also makes horizontal analysis much...

How/why would you distinguish between landing and re-entry? As far as I know, a safe re-entry ensures a safe landing due to controlling those factors. + you can add g-forces for manned missions, obviously. Maybe more specifically you could concentrate on 'decelerating' e.g. using fwd facing...