After a couple of practice matches, including a 3-1 win against SpVgg Unterhaching seven days previously, this was United's first friendly and came against a Tigers side who narrowly missed out on a place in the Championship play-offs in the previous campaign.
Alexander Isak, last season's top marksman for the Magpies with 25 goals, continued where he left off last term as he opened the scoring before Jacob Murphy added a second.
Ivor Pandur, the Hull goalkeeper, made a fantastic early saver to deny Joelinton after he powerfully met Isak's right-wing cross with his head.
Then a Murphy cross from the right narrowly evaded both Harvey Barnes and Isak - but Isak connected with another Murphy cross in the 32nd minute to put United in front.
Seven minutes later, Nick Pope produced a stunning reaction stop, diving to his left to somehow prevent Regan Slater from levelling.
And within seconds, United made it 2-0 as Murphy's low cross zipped into the far corner without anybody getting a touch.
In the 44th minute, Jamal Lewis centred from the left and Isak headed towards goal, but Pandur was able to hold.
And the Hull keeper was also able to gather a piledriver from Murphy after a free kick was played short to the winger.
Ryan Giles volleyed wide for the home side at the beginning of the second period but United - kicking towards their 4,500 travelling fans - almost added a third on the hour. A slick move involving Lewis, Barnes and Isak ended with the latter seeing a shot bravely blocked by Lewie Coyle.
Ryan Longman stung Pope's palms then, when Odysseas Vlachodimos replaced Pope for his United debut, Abdülkadir Ömür forced the Greece international into a smart save.
But - despite blooding a number of youngsters in the second half - Newcastle rarely looked like surrendering the clean sheet or the win.
Newcastle United: Nick Pope (Odysseas Vlachodimos 74), Joelinton (Trevan Sanusi 64), Harvey Barnes (Jay Turner-Cooke 64), Jamal Lewis (Anthony Munda 74), Alexander Isak (Ben Parkinson 64), Emil Krafth, Lewis Hall (Dylan Charlton 85), Tino Livramento (Alfie Harrison 64), Jacob Murphy (Johnny Emerson 74), Dan Burn (c), Jamie Miley (Ellis Stanton 79)
Subs not used: John Ruddy, Garang Kuol, Cathal Heffernan, Ciaran Thompson