GK
PHYSICS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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True
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False
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Either A or B
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None of the above
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Detailed explanation-1: -If an object is at rest, it means that there is no net force acting on it. An object at rest may still have forces acting on it, as long as they are balanced. When the forces acting on an object keep it at rest, the object is said to be in equilibrium.
Detailed explanation-2: -The force of gravity pulling down and the force of the table (FRICTION) pushing upwards on the book are of equal magnitude and opposite directions. These two forces balance each other.
Detailed explanation-3: -The table in return exerts a reaction force on the object equal to the magnitude of the weight but opposite in direction (Newton’s third law). Thus, the net force on the object is zero as two equal forces in opposite directions are acting on it and hence, the object remains at rest.