What is the second rak'ah after which we raise our hands, if the second (rak'ah) for the congregation is the first for the latecomer (to prayer)?

What the latecomer catches up with the Imam is considered the beginning of his prayer. It is recommended for him to raise his hands if he stands up from the first tashahhud, because the reason for raising the hands is standing up from the tashahhud, and this meaning applies to one who joins the Imam late. It should be noted that raising the hands is a Sunnah (recommended act) and not an obligation.