Compare and contrast energy, work and power.?

Answer 1

Energy is the ability to do work; it can be potential or actual.
Energy is a property of objects and systems that can perform work.
According to physics energy can never be lost only converted. If you convert mass into energy then you use the famous formula: E = mc^2.
The measurement depends on the type. For example kinetic energy can be measured in pounds or grams. Nuclear energy would be measured in radioactivity; Röntgens, and thermal energy would be measured in degrees C, F, or K.

Work is the action to move, lift or change the position of something
Work is the amount of energy required by a force to move something.
Work is measured in foot pounds or joules

Power is a measurement of energy; denoted by the formula: Power = work / time
Power is the amount of work done over a time interval.
Power is measured in watts, calories per hour, or horsepower.

So in a system there is usually some sort of energy; chemical kinetic, thermal etc, and this energy can be used to do work. When it is then the amount of work done over time is measured in units of power like watts or horsepower.

According to Wikipedia: http://en.wikipedia.org/wiki/Energy
“In physics and other sciences, energy (from the Greek ενεργός, energos, "active, working") is a scalar physical quantity that is a property of objects and systems of objects which is conserved by nature. Several different forms, such as kinetic, potential, thermal, electromagnetic, chemical, nuclear, and mass have been defined to explain all known natural phenomena.
Energy may be transformed from one form to another, but it is never created or destroyed. This principle, the conservation of energy, was first postulated in the early 19th century, and applies to any isolated system. According to Noether's theorem, the conservation of energy is a consequence of the fact that the laws of physics do not change over time. Although the total energy of a system does not change with time, its value may depend on the frame of reference. For example, a passenger in an airplane has zero kinetic energy relative to the airplane, but nonzero kinetic energy relative to the earth.”

According to Wikipedia: http://en.wikipedia.org/wiki/Mechanical_work
“In physics, mechanical work is the amount of energy transferred by a force. Like energy, it is a scalar quantity, with SI units of joules. Heat conduction is not considered to be a form of work, since there is no macroscopically measurable force, only microscopic forces occurring in atomic collisions. In the 1830s, the French mathematician Gaspard-Gustave Coriolis coined the term work for the product of force and distance.”

According to Wikipedia: http://en.wikipedia.org/wiki/Work
“Power has many meanings, most of which imply (a capacity for) control or force and may refer to:
In science, technology and mathematics:
- Power (physics) is the amount of work done or energy transferred per unit of time, cf. Force (physics)
- Motive power is power which moves something, such as output of a motor
- Electric power generation is the process of converting any form of energy to electrical energy, as in: e.g. power station, nuclear power, solar power, wind power, wave power, tidal power, geothermal power, hydropower. “