High School Is Newton's first law of motion applicable when walking?

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Newton's first law of motion states that an object at rest stays at rest and an object in motion stays in motion unless acted upon by an external force. While this law is always applicable, walking involves complex forces that create unbalanced external forces, making a straightforward application misleading. For instance, walking at a constant speed does not mean one won't tire, as energy is expended to overcome friction and maintain balance. Therefore, while the law provides a foundational understanding, it does not fully account for the dynamics of walking. Overall, Newton's first law does not apply directly to the act of walking due to the presence of these external forces.
Einstein60
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Is Newton's first law of motion applicable when walking?
 
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It's always applicable. But walking is a complicated process of using forces to drive yourself along and support yourself, so a naive application of it (something like "walking at constant speed shouldn't tire me out at all") won't work.
 
Einstein60 said:
Is Newton's first law of motion applicable when walking?
If we assume that Newton's first law only applies to a body with no unbalnaced external forces, then the answer is no, it does not apply to a person walking.
 

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