Help Please! Attachments to come!

Question

poofypenguin · Answer

Here's the question:

poofypenguin · Answer

Here's my first try:

poofypenguin · Answer

Here is my second try:

poofypenguin · Answer

Both of these answers are incorrect! Is there anybody out there that can point me in the right direction?

anonymous · Answer

One thing I'm thinking of now is that it is asking for the acceleration at the start of the burn before the 8kg of fuel has been fully spent and before the end of the 10s burn time.
It looks like you are solving for acceleration at the end of the burn (or rather the average acceleration during the 10s burn time).

poofypenguin · Answer

Alright, but i'm unsure if this is a momentum problem or a forces problem?

poofypenguin · Answer

Thus far i've been looking at it as a momentum problem, but that doesn't seem to be working...

anonymous · Answer

I don't think momentum will work here (not without calculus) because the mass is continuously changing over time.
Try it as a force problem.

poofypenguin · Answer

Alright! I'll give that a try! This might take a while...
But thanks so much for explaining it to me! :D