as long as you are not changing terminals in the connection, it is more than enough time in EWR. the other question is, are you going in a season where delays are likely (like now) which could affect the inbound but not the outbound (such at delays at your origin airport).
assuming EWR is the only timing, 50 minutes (even 35) is more than enough. if I was 45 or less, I would consider moving closer to the front of the plane to get off quicker. remember, the plane you are going to boards 30 minutes before takeoff, so at 50 minutes you really have 20 minutes to get off your plane, get to the other gate and get in line. Still, in EWR, without a terminal change, that's a lot of time.