I'm replying to myself, but invite people to discuss! I guess if the books are resting on the table, there's no Fnet bc there's no acceleration, they're just sitting there. But there's still a gravity force, otherwise, they'd go flying. So F=ma deals with acceleration aspect, and the Fg is purely gravitation force. In other words, Fnet=ma=0 indeed, but Fg does NOT equal zero. Fnet=Fnormal - Fg = 0 in this case.
Thank you for this phenomenal explanation! Are you still around? Would love to shoot you an email.
18:04 - I recognize the Fg=Gm1m2/r2 equation, but why is the Fg not F=ma=(mass of books)(-9.8)??
I'm replying to myself, but invite people to discuss! I guess if the books are resting on the table, there's no Fnet bc there's no acceleration, they're just sitting there. But there's still a gravity force, otherwise, they'd go flying. So F=ma deals with acceleration aspect, and the Fg is purely gravitation force. In other words, Fnet=ma=0 indeed, but Fg does NOT equal zero. Fnet=Fnormal - Fg = 0 in this case.
Wow! I was making this mistake, and this was helpful! Thank you! (15:53)
thank youuuu
yess