Final answer:
The concepts discussed include gravitational force, normal reaction force, and Newton's first law of motion. Gravitational force is a mutual attraction between masses, the normal reaction force acts perpendicular to contact surfaces, and external force is required to alter an object's motion in space.
Step-by-step explanation:
The student's question "(O) hold down to disable 'gravity-weighted'? 1) True 2) False" seems to be asking about a specific function on an unspecified platform, which might not directly relate to Physics concepts. However, considering the additional information provided, we can infer that it's related to gravitational force and address some fundamental Physics principles in our answer:
True or false: Gravitational force is the attraction of the mass of one object to the mass of another. This statement is True. Gravitational force is indeed the mutual force of attraction between any two objects with mass.
As for the book balanced by a standard 1-kg iron weight on Earth, if this setup is taken to the moon, the balance would still be level. This is because, although the gravitational force is much less on the moon, it affects both the book and the iron weight equally, resulting in a level balance. However, it's important to understand that the balance scale measurements would be different since the gravity on the moon is weaker than Earth's.
The statement that normal reaction is the force that opposes the force of gravity and acts in the direction of the force of gravity is False. The normal reaction force actually acts perpendicular to the surface in contact with an object, not in the direction of the force of gravity.
If a boy pushes a box weighing 300 N up a ramp that is 1.0 m high and 3.0 m long, it does not necessarily mean he was pushing with a force of exactly 100 N. This overlooks the concept of mechanical advantage and the work done against gravity, so this statement is False.
In the context of free fall and apparent weightlessness, both in an orbiting spacecraft and a free-falling aircraft, the condition is the same because both are free-falling, resulting in an apparent weight of zero. An astronaut, far from any large mass, would feel weightless, but their mass remains the same.
True or false: An external force is required to set a stationary object in motion in outer space away from all gravitational influences and atmospheric friction. This statement is True, based on Newton's first law of motion. Without an external force, an object at rest will stay at rest.