The last thing we'll cover in this section is center of mass. The center of mass of an object (or a system of objects) is the mass-weighted average position of all of the parts of that object (or all of the objects in that system).
Put another way, the center of mass of a group of objects is the sum of each object's position multiplied by its mass, all divided by the total mass. The same is true for a single object, but instead of a group of "individual" masses we are looking at how the mass is distributed (or spread out) across that object. Don't worry if that seems confusing, it'll make more sense after a few examples.
Also, remember projectile motion? Although we talked about an entire object following a trajectory, we were really describing the motion of the object's center of mass.
We'll revisit center of mass in the lesson on rotational dynamics, and talk about the center of gravity and how objects balance on their center of mass.
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The last thing we'll cover in this section is center of mass. The center of mass of an object (or a system of objects) is the mass-weighted average position of all of the parts of that object (or all of the objects in that system).
Put another way, the center of mass of a group of objects is the sum of each object's position multiplied by its mass, all divided by the total mass. The same is true for a single object, but instead of a group of "individual" masses we are looking at how the mass is distributed (or spread out) across that object. Don't worry if that seems confusing, it'll make more sense after a few examples.
Also, remember projectile motion? Although we talked about an entire object following a trajectory, we were really describing the motion of the object's center of mass.
We'll revisit center of mass in the lesson on rotational dynamics, and talk about the center of gravity and how objects balance on their center of mass.
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