timothy42b
Eagle Member
Okay 201 isn't out yet, but I'll be ready.
What really really causes spin? And how do we know that's the right answer? (If it is just one answer; I can think of about four possible contributors).
What are the forces that causes the disc, and where are they applied? I haven't seen a convincing answer. Maybe I'm the only one who doesn't know.
I know some obvious theories about ball golf have turned out to be wrong. The golf ball spin (average player, about 3300 rpm, tour player about 2700) is not caused by friction on the grooves, but by the moment induced by striking the ball below the center of mass.
FWIW, I didn't see an answer in the Hummel thesis from 2003. The bent arm throws she measured were what they'd call a pass in ultimate, or an up shot in disc golf. Energy for linear velocity was about 14.1 joules and rotational was 2.54. Josh from Overthrow with that high tech disc posted throws averaging 53.48 mph and 1086.65 rpm, which is 50.013 joules linear and 15.215 joules rotational. (feel free to check my math.) I used Josh because he's not an elite thrower but not a novice either, and he just posted the data from his new toy.
Will it help me throw better? Probably not, but it relates to a couple things discussed recently.
What really really causes spin? And how do we know that's the right answer? (If it is just one answer; I can think of about four possible contributors).
What are the forces that causes the disc, and where are they applied? I haven't seen a convincing answer. Maybe I'm the only one who doesn't know.
I know some obvious theories about ball golf have turned out to be wrong. The golf ball spin (average player, about 3300 rpm, tour player about 2700) is not caused by friction on the grooves, but by the moment induced by striking the ball below the center of mass.
FWIW, I didn't see an answer in the Hummel thesis from 2003. The bent arm throws she measured were what they'd call a pass in ultimate, or an up shot in disc golf. Energy for linear velocity was about 14.1 joules and rotational was 2.54. Josh from Overthrow with that high tech disc posted throws averaging 53.48 mph and 1086.65 rpm, which is 50.013 joules linear and 15.215 joules rotational. (feel free to check my math.) I used Josh because he's not an elite thrower but not a novice either, and he just posted the data from his new toy.
Will it help me throw better? Probably not, but it relates to a couple things discussed recently.