What is the ruling if one joins the salah and is unable to complete or recite surah fatiha before the imam goes for rukko’. Is this rakkah valid or has to repeat after the imam completes the jamaat
If this was a loud rakah then the recitation of Fatiha by the Imam is sufficient for the followers as well.
If this was a silent rakah and if you joined before the imam went into ruku then you must finish the Fatiha quickly and then go to ruku. This won’t take more than few seconds.