Force/pressure exerted from rubber band

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pryphnoq
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If you stretch a rubber band around a pole, the band exerts a force onto the surface of the pole (F1 in figure 1). Is it possible to calculate this force if I know the force needed to stretch the rubber band to the same total length as the circumference of the pole? That is to say:
1. I know the force F2 in figure 2
2. The total length of the rubber band is the same in figure 1 and figure 2

Can I calculate the force F1? Is it meaningful to talk about force, or should one talk about the pressure instead?
 
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  • Diagram comparing a rubber band wrapped around a circle (fig, 1), with inward force F1 pointing up from the centre of the circle's bottom edge, and the band stretched straight (fig, 2), pulled outward at both ends by forces labelled F2.
    rubberband.png
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pryphnoq: Yes, it would be more relevant to talk about the contact pressure underneath the rubber band, which would be p1 = F2/(r*b), where r = pole radius, and b = rubber band width (when stretched). The total resultant force of this pressure, on one half of the pole circumference, would be, F1 = 2*p1*r*b = 2*F2.
 
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