Machine's operate by tranforming a small force applied over a long distance to a strong force applied over a short distance, enabling them to carry heavy loads when operated with weak forces.
1d1 = W2d2
Work and Energy
Energy is an objects capacity of performing work. e.g. raising an object increases its potential energy that it will unleash when it is dropped.
Forms of energy that objects may possess.
Energy due to motion
Energy due to position
Energy stored through stretching and squeezing
Energy of particles carrying electric charge
Energy due to heat
Energy that can be released from an atom with an unstable nucleus
Energy released when chemical substances undergo chemical reactions
Energy can be moved between objects and transferred from one store to another.
Examples of Energy Transfer
- Light or soundwaved emitted by one object are absorbed by another
- Heat transfer from a hot to a cold object
- An object's potential energy becoming kinetic energy as it falls
Conservation of Energy
The total energy of an isolated system stays the same as its objects exchange energy with each other (regardless of the systems specific state).
Energy and Power
Power (Watts) is rate of energy transfer.
Efficiency and Power
Machine's have input and output powers that are almost never equal due to energy being lost to waste heat. A machine's maximum efficiency is .