I had the chance to collect data from the elite women's jumps from last week's world championships. I would post here some neat diagrams, but as the forum accepts only url input, I don't bother. However, some take-home messages:
1) The range of jump heights is surprisingly similar for 2A, and 3F and 3L on the other hand, ranging from some 30 cm to over 50 cm. This means that the axels spin slower.
2) The F/m ratio can be calculated without knowing the performer's weight. However the dip height (from how deep you jump) has to be assumed. Assuming that the dip is some 16% of the person's height, the F/m ratios for women's jumps range in 22-30 N/kg.
3) One can only roughly calculate what this means for the forces involved. The vertical force at the take-off is typically >1000 N and sometimes much more. The tangential forces (the ones which make you spin) are likely to be somewhat smaller. I'd guess that a typical value is some 400 N for 2A and a little over 500 N for 3F or 3L. However, this is subject to many uncertainties.
edit: Part of the forces generated may come from the slide before the take-off, so this is not the same thing as a static squat. And what if it was? "Anybody" can jump 45 cm at home, so suddenly, that doesn't seem such a limiting factor. But not everyone can do it while skating, spinning and not falling.
So, I finally kind of accept the traditional rule: It's art as much as it's sport.
1) The range of jump heights is surprisingly similar for 2A, and 3F and 3L on the other hand, ranging from some 30 cm to over 50 cm. This means that the axels spin slower.
2) The F/m ratio can be calculated without knowing the performer's weight. However the dip height (from how deep you jump) has to be assumed. Assuming that the dip is some 16% of the person's height, the F/m ratios for women's jumps range in 22-30 N/kg.
3) One can only roughly calculate what this means for the forces involved. The vertical force at the take-off is typically >1000 N and sometimes much more. The tangential forces (the ones which make you spin) are likely to be somewhat smaller. I'd guess that a typical value is some 400 N for 2A and a little over 500 N for 3F or 3L. However, this is subject to many uncertainties.
edit: Part of the forces generated may come from the slide before the take-off, so this is not the same thing as a static squat. And what if it was? "Anybody" can jump 45 cm at home, so suddenly, that doesn't seem such a limiting factor. But not everyone can do it while skating, spinning and not falling.
So, I finally kind of accept the traditional rule: It's art as much as it's sport.
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