The physics spring in senior high school is like this, and the stiffness coefficient algorithm is like this, but I don't even understand how this spring is hung. Can you explain it?

Is this a pulley? Only the two ends of the pulley are connected to the ceiling, and the ropes on the left and right sides of the pulley become springs with different stiffness coefficients. What is needed is the stiffness coefficient of the whole system as a spring.

As for the formula, we have f1= k1x1= f2 = k2x2, because to keep the two ends balanced and prevent the spring from moving and stretching left and right.

As for the resultant force f = f1+F2 = k1x1+k2x2; At this time, the falling height of the pulley is X=(X 1+X2)/2. Note that the spring can stretch here, but the length of the left and right stretching is not necessarily the same, because the pulley can roll, and the longer it is pulled, the more it rotates.

Finally, the K=F/X of this system can be obtained as k = 4k 1k2/(k 1k2) after some changes.