Windtest of feathers for arrows
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Windtunnel speed 50 m/s. |
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Arrow Easton ULTRA LITE 1811 29,5 inch |
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Arrow |
Weight m (kg) |
Drag force F(N) |
Rev/sek |
a |
After 18m |
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1 |
0.0133 |
0.235 |
54 |
17,7 |
44,3 |
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2 |
0.0134 |
0.255 |
36 |
19,0 |
43,9 |
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3 |
0.0133 |
0.216 |
<5 |
16,2 |
44,8 |
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4 |
0.0133 |
0.206 |
11 |
15,5 |
45,0 |
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5 |
0.0136 |
0.245 |
40 |
18,0 |
44,2 |
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6 |
0.0134 |
0.255 |
16 |
19,0 |
43,9 |
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7 |
0.0131 |
0.199 |
44 |
15,2 |
45,1 |
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Drag force F for Arrow 1
is 0.235N
Weight m (kg) is 0.0133 kg
Arrow speed loss a in m/s/s
a=F/m a=0,235/0,0133=17,7 m/s/s
Arrow speed loss a in
m/s/s.
If Arrow 1
is shot with an
initial velocity of 50 m/s,
it will be slowed down to 32,3 m/s
after 1s and app. 41 m.
If Arrow 7 is shot with an
initial velocity of 50 m/s,
it will be slowed down to 34,8 m/s
after 1s and app. 42,5 m.
The target is at the same
level, and the calculations are
simplified, (the drag is supposed to be independent of
velocity from 50 to 30 m/s and the drag effect of fish-
tailing is ignored).
For more info: bertil@mvvf.net