The Gunners overcame a shaky start in which they spent most of the first half on the back foot to record back-to-back Premier League away wins for the first time since May 2017.
A stunning Granit Xhaka free-kick and a goal for Mesut Ozil on his 200th Arsenal appearance ensured the points for the visitors at St James' Park despite Ciaran Clark's late header.
Much was made of Arsenal's struggles on the road last season as they won just one away game in the league after the turn of the year.
Wins at Cardiff City and Newcastle may suggest Arsenal have found a formula for success on their travels, but Emery is not yet satisfied.
"The first half we couldn't control the match like we wanted. We need to impose our ideas, but we conceded a lot of chances for the counter-attack," said Emery.
"The second half, the balance on the pitch was better. We didn't concede the transition as easy.
"The key was the first goal, it gave us the confidence to improve on the match.
"One challenge is to have better performances away, to be more competitive, to have chances to win. This way is about consistency.
"We are happy for two victories away, but we need to continue to improve [and to be] more competitive."
Goalkeeper Petr Cech endured another game where he was uncomfortable on the ball and, asked if he could start Bernd Leno for Thursday's Europa League clash with Vorskla Poltava, Emery replied: "Yes, we are going to change and use a lot of players for different competitions.
"Every competition for me I have respect for. Normally I will use a different keeper for the competition."
Newcastle's four defeats have come against Tottenham, Chelsea, Manchester City and Arsenal and all by a 2-1 margin and Rafael Benitez, who saw captain Jamaal Lascelles forced off with an ankle injury at half-time, accepts a return of one point from five games was always a possibility from such a tough opening run.
"I'm not worried. It is nothing we weren't expecting. Maybe Cardiff is a game we should have won," he said. "The reality is against the top side you can lose. We have lost to small margins – the only positive is they are small margins.
"Lascelles twisted his ankle in the warm up. We'll see, the doctor said to check in a couple of days."