Answer :
The magnitude of the force that the object exerts on the child is 100 N.
option C is the correct answer.
What is Newton's third law of motion?
Newton's third law of motion states that for every action there is an equal and opposite reaction. In other words, action and reaction are equal and opposite.
Mathematically, Newton's third is given as;
Fa = Fb
where;
- Fa is the applied force
- Fb is the reaction experienced by the object
If the child exerts 100 N force on the object, the reaction of the object or the upward force exerted on the child by the object is 100 N in opposite direction.
Learn more about Newton's third law of motion here: https://brainly.com/question/25998091
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