4K Blu-ray

I just want to know if I insert a 4K Blu-ray movie into a normal Blu-ray player, will it play? I know it won't be in 4K, but will it at least still work? Specifically trying to use a PS3 (because of the built-in Blu-ray player) to play a 4K Blu-ray movie.

Seems like my 80 " Vizio is on the way out. Would like to upgrade to a 4K HDR TV and get the 500 GB Xbox One S for the 4k blu ray drive and occasional gaming, its the cheapest blu ray drive by $100 plus I can play games. But I have several questions. Which 4K HDR TV 70" or more is the best for...