Predictions about why the object does not accelerate downward are (1) the bonded molecules of the object are repelled upward by the bonded molecules of the ground with the same magnitude as the gravitational force downward on the object, and (2) the normal force is exerted upward on the object from the ground with the same magnitude as the gravitational force downward on the object.
The normal force is simply the force that two surfaces in contact exert to each other to prevent themselves from passing through each other. Since the normal force is a contact force, two surfaces that aren't in contact can't exert a normal force on each other. The normal force will be as large as necessary to make net force equal zero.
The normal force is generated by the electromagnetic force: the electrons in an object are pushing against the electrons in another object.
Learn more about an example of finding the normal force here: https://brainly.com/question/28788588
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