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Why do objects on Earth usually stop moving even though Newton’s first law says motion continues?

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A diagram of a cylindrical vessel containing gas, with a movable piston held down by a weight. Countless small dots beneath the piston represent gas particles in rapid, random motion, illustrating Bernoulli's model of gas pressure. — physics As conceived by Daniel Bernoulli in *Hydrodynamica* (1738), gases consist of numerous particles in rapid random motion. He assumed that the pressure of a gas is produced by the direct impact of the particles on the walls of the container.

Objects on Earth do not stop moving because Newton’s first law is incorrect; rather, they stop because they are acted upon by external, unbalanced forces that oppose their motion.12

While the law of inertia states that an object will maintain its state of rest or uniform motion unless compelled to change by a force, our daily experience on Earth is dominated by forces such as friction and air resistance. These forces act in the direction opposite to an object's motion, effectively serving as the "unbalanced force" that causes a moving body to come to rest.123

In the absence of these resistive forces, an object would continue to move indefinitely in a straight line at a constant speed. The observation that objects tend to stop when not pushed is not a contradiction of Newtonian mechanics, but a practical demonstration of how environmental forces constantly interact with moving matter.12