Despite the perception that Obi-Wan was Luke's mentor who taught him in the ways of the Force, it seems like they only had a minute of actual Jedi training. This was on the Millennium Falcon as it made its way from Tatooine to the Death Star.
Han, near the start of the scene, brags about just escaping the Imperial ships above Tatooine, with the jump to light speed:
Han: Well, you can forget your troubles with those Imperial slugs. I told you I'd outrun 'em.
Luke gets to try out his lightsaber with the training droid, including with his blast shield down. They have a short conversation about the nature of the Force, and Han gets to express his skepticism. Meanwhile Chewie, R2-D2 and C-3P0 play their holographic board game.
At the end of the same scene:
Han: Looks like we're coming up on Alderaan.
Does it really take just a few moments to get from Tatooine to the Death Star (where Alderaan would have been)? Are they really moving "merely" at light speed or what?