7 : Deflection forces
Where a rope is initially anchored under tension and then deflected in the middle ( pulled sideways somehow ) the force applied at each anchor can be five times or more larger than the deflecting force .
The ‘ straighter ’ the rope and the more static the rope , the larger the force applied at the anchors will be .
Graph of included angle against ratio of load applied at each anchor point for a rope deflected by a load
Ratio of deflected load applied at each anchor
6
5
4
3
2
1
0 0 ° 10 ° 20 ° 30 ° 40 ° 50 ° 60 ° 70 ° 80 ° 90 ° 100 ° 110 ° 120 ° 130 ° 140 ° 150 ° 160 ° 170 ° 180 ° Included angle
Force applied
Note that as the included angle approaches 180 ° the force applied tends toward infinity . No rope could ever be sufficiently static that a perfect 180 ° included angle would be possible .
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