Conservative forces are forces independent of the path of motion, such as gravity or electrostatic interactions between particles. If you then dump the water, it will flow down to the ground. You stored potential energy in the water by acting against the gravitational field i. When you released it from the bucket, that water expended its potential energy as kinetic energy under the action of gravity. An interesting property of mechanical energy is that in an isolated, ideal system, it is constant.
In real systems, however, non-conservative forces such as friction or air drag will eventually sap mechanical energy, turning it into heat.
Do you know what has a lot of chemical energy? But , if you want something with a lot of chemical energy, you need dynamite.
Our bodies break open bonds during cellular respiration to obtain this type of energy. Chemical energy is also released when we blow up a stick of dynamite, when feeding wood into a fireplace, when pressing the gas pedal , and as the battery in your smartphone generates electricity. If a substance can react with another to undergo a transformation through a chemical reaction, it has chemical energy. That energy is equal to the difference between the energy content of the products and the reactants if the temperature remains constant.
As long as a chemical change takes place, it will either generate or absorb energy. Combustion, that merry thing keeping the world going, is a superb example of chemical energy being released. Fire is what happens when oxygen molecules bind to various compounds, releasing the energy in their bonds.
This type of energy is the result of the flow of electric charge through a conductor due to electrical attraction or repulsion between charged particles. Electrical energy can be potential static electricity or kinetic when the charges are in motion, i.
It is generated from differences in electrical potential between two or more objects in a given system. It can also be generated by kinetic force, though the movement of a copper wire loop or disk around the poles of a magnet.
Generally speaking, this works because the electrons in the copper wire are free to move about as they please. Each electron is negatively charged, so it will be attracted to positively-charged particles and pushed away by other negatively-charged particles.
You can also see this as the electron attracting certain particles while repulsing others — in other words, each charged particle has a tiny electric field around it that can exert a force on other particles, causing them to move force over distance is physical work. Generators function by supplying force to move these charged particles around, causing them to move other charged particles, in turn, generating electricity.
A moving charged particle will always generate a magnetic field. A moving magnetic field always induces an electric current in a conductor.
Nuclear energy is released or absorbed, mind you whenever a nuclear reaction, or radioactive decay, occurs. A common scene in some parts of the countryside is a "wind farm. The mechanical energy of the moving air gives the air particles the ability to apply a force and cause a displacement of the blades. As the blades spin, their energy is subsequently converted into electrical energy a non-mechanical form of energy and supplied to homes and industries in order to run electrical appliances.
Because the moving wind has mechanical energy in the form of kinetic energy , it is able to do work on the blades.
Once more, mechanical energy is the ability to do work. As already mentioned, the mechanical energy of an object can be the result of its motion i. The total amount of mechanical energy is merely the sum of the potential energy and the kinetic energy. This sum is simply referred to as the total mechanical energy abbreviated TME. As discussed earlier, there are two forms of potential energy discussed in our course - gravitational potential energy and elastic potential energy.
Given this fact, the above equation can be rewritten:. The diagram below depicts the motion of Lee Ben Fardest esteemed American ski jumper as he glides down the hill and makes one of his record-setting jumps. The total mechanical energy of Lee Ben Fardest is the sum of the potential and kinetic energies. The two forms of energy sum up to 50 Joules. Notice also that the total mechanical energy of Lee Ben Fardest is a constant value throughout his motion.
There are conditions under which the total mechanical energy will be a constant value and conditions under which it will be a changing value. This is the subject of Lesson 2 - the work-energy relationship. For now, merely remember that total mechanical energy is the energy possessed by an object due to either its motion or its stored energy of position. The law of the conservation of energy states that energy is neither created nor destroyed.
Instead, it is simply transferred from one type of energy to another, or from one form of energy to another. The difference between mechanical energy and kinetic energy is that kinetic energy is a type of energy, while mechanical energy is a form of energy. Work can be defined as the process of energy transfer whereby a force acts upon an object to cause a displacement. If an object is moved, then work has been performed. Work requires three things: a force, a displacement and a cause.
For example, if you picked up a book and placed it on the top shelf of a bookshelf, the force would be you lifting the book, the displacement would be the movement of the book and the cause of the movement would be the force you applied. There are two types of energy: potential and kinetic. Potential energy is energy that is stored in an object due to its position.
This type of energy is not in use but is available to do work. For example, the book possesses potential energy when it is stationary on the top of the bookshelf.
Kinetic energy is energy that is possessed by an object due to its motion.
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