Does A Man Gets To Know That His Wife Is A Virgin Or Not Simply By Having Sex With Her?

Sorry, the days of the hymen being intact on the wedding night are long gone.  The hymen is usually worn down long before marriage due to the physically active lifestyles of girls and young women today.  I guess you will have to take her word for it -- and isn't trust what you want out of your marriage?  (By the way, women don't usually view their lovemaking with a husband as "simply having sex" -- an attitude which seems to contradict your concern for her virginity).