Imagine two people of equal mass are pulling a rope in different directions. At the midpoint on the rope, why is the force acting not equal to 0? Its the same issue if I hold two newtonmeters, attach them to each other, then I pull. I receive the same force readings on both. Could someone please explain this phenomenon? I am very confused.

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    $\begingroup$ Tension has a bi-directional character to it (based on the so-called stress tensor). So, on either side of the center, the pulls are of the same magnitude, but in opposite directions. The net force on the center is zero. $\endgroup$ – Chet Miller Sep 21 '19 at 12:36

The net force acting on every part of a stationary rope under tension is indeed 0. It must be, because it's not moving and $F_\text{net}=ma$ always holds.

Your newtonmeters are not measuring "net force", they are measuring the tension in the rope. E.g. if they are spring gauges they measure it because the springs will expand until the restoring force of the spring trying to contract matches the forces with which it is pulled apart, i.e. their whole priniciple of measurement is based on reaching the state where the net force acting on them is 0!


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