According to Tsiolkovsky's rocket equation, it is possible to calculate the delta-v of a multistage rocket if you know the characteristics (specific impulse, initial and final masses) of each stage of the rocket.

My questions are:

• A rocket has a vacuum and a sea-level specific impulse. Which one of these two should I use to calculate the total delta-v of a multistage rocket?
• Tsiolkovsky's rocket equation is applicable for a rocket which is not subject to external forces. How do I "correct" the delta-v for lower-stage rockets? What are the delta-v losses that should be accounted for?

Resources (books, papers, etc.) that add more info to the answers would be appreciated.

According to Tsiolkovsky's rocket equation, it is possible to calculate the delta-v of a multistage rocket if you know the characteristics of each stage of the rocket. In my case, the only characteristics that I have found on a rocket's data-sheet/catalog were the following: vacuum specific impulse, initial and final masses of each stage of the rocket.

My questions are:

• A rocket has a vacuum and a sea-level specific impulse. Which one of these two should I use to calculate the total delta-v of a multistage rocket?
• Tsiolkovsky's rocket equation is applicable for a rocket which is not subject to external forces. How do I "correct" the delta-v for lower-stage rockets? What are the delta-v losses that should be accounted for?

Resources (books, papers, etc.) that add more info to the answers would be appreciated.