Question

in what case the forces will subtraction?​

Answer 1

In general, whenever forces act on an object in opposite directions—like the book on the table—the net force is equal to the difference between the two forces. In other words, one force is subtracted from the other to calculate the net force

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Answer 2

Answer:

Thus, subtracting the two vectors is the same as adding vector A and vector B's negative (i.e., B). The vectors B and –B will have the same magnitude, but -B's direction will be opposite to that of vector B

When forces act in opposite directions, they are combined by subtracting the smaller force from the larger force. The direction of the resulting force (resultant) is the direction of the larger original force.