Yeah, it's one of those "evil US exceptionalism" things, where Americans work a heck of a lot. If you're working less than 40hrs/wk, you're working part-time. In most professional/knowledge type industries (tech of all kinds, at the least) 40hrs is a day-dream that people would love to work, rather than the 50-100 they actually work.

Of course, this is presuming you hate work. I spend more than a third of my life doing it and it's something I really enjoy. A man is defined by his hard/smart work.

The typical work-day in the US starts at 8am and ends at 5pm. Throw in at least an hour or two for commute in the morning and an hour or two for commute in the evening. Possibly throw in some work-from-home after you kick off your shoes and walk through the door at home, too.