I'm using Tor 0.2.8.9 on Mac. I've come to realize that Tor exit nodes are easily identified, and as such, someone can block access to a Tor browser by simply blocking the IPs correspoding to those exit nodes. I've read a little bit about bridges and my quesiton is, does using a bridge with Tor prevent people from knowing what exit node you use?
nope, not at all. Using a bridge is a way to enter the Tor network, it has literally nothing to do with exiting it: you will have the IP address of the exit node used. When any detector like TorDNSEL will probe the exit node - it will flag it(it's outbound IP, in particular) as an exit. Bridges are a great helping hand in entering the network, but it's not related to the exiting mechanism at all. Even if you will use bridges on the exit node - it won't change it's outgoing IP. A thing that can potentially help it is a VPN on an exit node side: of course, it won't change the exit node's id/hash in Tor network, but it can change it's outgoing IP if you will switch your VPN connections to obtain a different outbound IP for an exit node. However - it seems to me that such kind of hiding techniques won't help greatly. The whole architecture of Tor network is to protect the client, or the incoming connection. Other things like Hidden Services and Exit nodes are much less protected from a tracking techniques.