No, inertia does not depend on net force. Inertia is an object's inherent resistance to changes in its state of motion.
Here's a breakdown:
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Inertia Defined: Inertia is a property of matter that describes how much an object resists changes to its velocity (speed and direction). The more massive an object is, the greater its inertia. It is a characteristic of the object itself.
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Net Force Defined: Net force is the sum of all forces acting on an object. It is what causes an object to accelerate (change its velocity).
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The Relationship (or Lack Thereof): An object possesses inertia regardless of whether or not a net force is acting on it. If no net force is acting (forces are balanced or absent), the object will maintain its current state of motion due to its inertia: staying at rest if it's at rest, or moving at a constant velocity if it's already moving. A net force overcomes inertia, causing a change in motion (acceleration).
Analogy:
Imagine a bowling ball and a tennis ball. The bowling ball has more inertia than the tennis ball because it has more mass. It takes more force to start the bowling ball moving or to stop it once it's in motion. This is true regardless of whether you are actively pushing on either ball. Their inertia is a fundamental property based on their mass. Applying a net force is what would overcome that inertia, resulting in acceleration.
Example:
A stationary car has inertia. It requires a net force (from the engine overcoming friction and air resistance, or being pushed) to start moving. The car still has inertia even when it's at rest. If you remove all forces from a moving car (ideal scenario), the car will continue to move with constant velocity due to its inertia.
