Final answer:
The net force when two unbalanced forces act in opposite directions is the difference between the two forces. This is due to Newton's second law of motion. Hence, the correct answer is b) The difference of the forces
Step-by-step explanation:
When two unbalanced forces act on a body in opposite directions, the net force is equal to: b) The difference of the forces. This is because each force cancels out some of the other, leaving you with the balance of the force that is stronger. For example, if there are two forces of 10 N and 5 N in opposite directions, the net force would be 5 N, which is the difference between the two forces. This principle is part of Newton's second law of motion which states that acceleration is produced when a force acts on a mass. Therefore, the net force is equal to the mass of the object times its acceleration (F=ma).
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