It looks like you're exploring concepts related to motion and forces on Earth. Let’s clarify a few points:
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Need to Apply a Force: According to Newton's first law of motion, an object at rest will stay at rest, and an object in motion will stay in motion at a constant velocity unless acted upon by an unbalanced force. Thus, to move a stationary object, you need to apply a force to overcome inertia.
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Movement Without Applied Force: Bodies can indeed move without an external force being applied, such as when they are already in motion (e.g., a rolling ball). However, if they are in motion, an external force (like friction or air resistance) will eventually slow them down and stop them unless another force is applied.
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Friction: Friction is a force that opposes motion. If you want to move an object (like a box), you need to apply a force that is greater than the friction between the object and the surface it's on. Once you overcome that friction, the object will start to move.
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Acceleration: When you apply a force to an object, it will accelerate according to Newton's second law (F = ma), where F is the net force applied, m is the mass of the object, and a is the acceleration produced.
In summary, a force is required to move an object because it either needs to overcome inertia, friction, or both, depending on the situation. If you have more specific scenarios in mind, feel free to elaborate!