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Дата изменения: Thu Jan 21 19:48:39 1999
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Fundamentals of Mechanics

ENERGY FUNDAMENTALS

Mechanics: Description of forces and energies associated with moving objects; a manifestation of forces acting on material objects

Components of Mechanics:

Your intution already has physics knowledge

Real Physics looks like this

Our Version of Physics is more like the following:

1. You can't move a building
2. A train accelerates more slowly than a motorcycle
3. What goes up must come down
4. On the freeway you would rather have a headon collision with a mosquito instead of a semi
5. You get tired after climbing a long flight of stairs


Newton described mechanics fully in terms of three laws: constant velocity with no forces, F= ma, equal and opposite reactions

Newton's Three Laws:

Let's do an experiment with forces and masses:

What is Energy?

Energy comes in many forms, kinetic, potential (stored), heat, etc. Energy is always conserved. It is not created or destroyed but is just transformed from one form to another.

Energy = FORCE * DISTANCE

Power = Energy/Time
Energy = Power * Time

A kilowatt is a unit of Power

A kilowatt hour is a unit of Energy

Two Main Kinds of Energy

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