Energy and momentum are important ideas in physics, but they work in different ways.
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What Are They?:
- Energy is what allows things to move or do work. For instance, when something is moving, that's kinetic energy.
- Momentum is how much motion something has. You can think of it as being calculated with this formula: momentum (p) = mass (m) × speed (v).
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How They Work in Systems:
- Energy can change from one type to another. For example, it can go from kinetic energy (like moving) to potential energy (like stored energy).
- Momentum stays the same in closed systems. That means no outside forces are acting on the objects.
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Examples:
- In a perfect elastic collision (like two pool balls hitting each other), both energy and momentum stay the same.
- In a perfect inelastic collision (like a car crash where cars stick together), only momentum stays the same; energy is lost.
Understanding these differences makes it easier to see how objects interact in the world!