Didactic teaching often seems to demand that ideas should be given precise definitions, but energy can be a slippery concept just when we think of us have grasped it some new example is likely to elude of us. Furthermore, even though it would be nice if the concept of energy were immutable, the history of physics shows that conceptions change. Ideas about energy are still developing and cropping up in new contexts. For example, physicists of half a century ago would have a hard time understanding the modern, somewhat speculative, concept of a” dark energy” that drives the expansion of the cosmos. one of the best straightforward explanation of power was agreed by Nobel laureate Richard Feynman.
Energy is not something detectable but a number that has to be designed using a complete set of policy. Feynman used a metaphorical story about a mother counting a kid’s toy blocks. Power to Choose an underlying principle, Understanding energy 3conservation of blocks, leads Mother to look in more and more places and find new ways to account for blocks to make sure that the conservation principle works.
Some part of energy work
At worst they are just plain wrong. The main argument against such a definition comes from thermodynamics. In thermodynamics, work takes on a meaning which is broader than the “force times distance” concept of classical mechanics. It refers either to a process of energy transfer or to the energy being transferred. Understanding energy 4texts are not clear which of those two concepts they mean and often use them interchangeably, but when work appears in equations it always has the dimensions of energy. The catch is that not all energy can produce work; according to the second law of thermodynamics, there is always some part of the energy of a system that cannot produce work.
- Energy is an attribute of a system that may consist of one or more objects.
- Changes in the energy of a system can, in principle, be calculated, but it is usually not feasible to assign a value to the total energy of a system.
- Whenever the energy of a system increases there is a corresponding decrease outside the system.
- Changes in the energy of a system can be tracked across the system’s boundary.
- There are only two basic kinds of energy: kinetic energy (KE) and potential energy (PE).
- Kinetic energy is associated with motion.
- Potential energy is associated with interactions between objects.
- Potential energy can be defined only for a system consisting of two or more parts.
- Electromagnetic PE can be described as being stored in and transmitted by the electric and magnetic fields.
- Chemical changes involve changes in electromagnetic PE.
- When a hot body and a cold body are in contact, the hot body loses energy and the cold body gains energy. Here are some starters.
- Energy is not given off by crystals.
- Energy is not a feeling of well-being.
- Energy does not cause things to happen
- In spite of what it says on my gas bill, the gas company does not sell energy.
Energy and work many texts give neatly packaged definitions of energy such as “energy is the capacity to do work”.The main argument against such a definition comes from thermodynamics. In a meaning which is broader than the “force times distance” concept of classical mechanics. It refers either to a process of energy transfer or to the energy being transferred.