Two horizontal strings are attached to a block, resting on a frictionless surface as shown below. A force of 100N pulls on one string. The block does not move. Find the value o
force, F on the other string
ON​

100N in the opposite direction

Explanation:

as the block is not moving, we can apply the formula f=ma where the total force is equal to the mass times accelaration, since the block is not moving, the net force is zero meaning that the other force is completely cancelling out the force of 100N, or to put it in a maths equation, 100-force=0 as the block is stationary. we can therefore assume that the force cancelling the 100N out is equal to it and therefore 100N in the opposite direction

explanation:

newton's third law, for every action there is an equal and opposite reaction.