Machine Effectiveness The percentage of effort put into a machine by the user (input work) that is converted into work done by the machine is referred to as efficiency (output work). Because some of the input work is utilized to overcome friction, the output work is always less than the input work. As a result, efficiency is never 100 percent. However, high-efficiency machines can achieve very high levels of effectiveness--that is, their output work per unit of input work.
For example, an efficient hand-powered drill could be made much more powerful if it used an electric motor instead of human power. Such a machine would have very high efficiency because only a small fraction of the energy supplied to the motor is lost to heat. On the other hand, an efficient electric motor designed for use in a hand-held tool could not be made any more compact or lighter weight because it would be ineffective without a human being to operate it. Thus, its efficiency would be low because a large amount of energy is lost through resistance heating.
In general, the efficiency of a machine depends on how effectively its parts cooperate with one another. If part of the input work is wasted in doing unnecessary work (such as moving non-moving parts), then the machine will be inefficient. For example, if a hand-operated jack fails to lift the load all the way up before releasing it, then some of the load's upward force remains in the form of residual downward pressure that has to be handled by the person lifting it.
Machine Effectiveness Because some of the input work is utilized to overcome friction, the output work is always less than the input work. The closer a machine's efficiency is to 100 percent, the better it is in reducing friction.
The amount of effort or energy saved in a process is measured as efficiency. Work or energy is wasted in many processes, for example, as waste heat or vibration. The efficiency is calculated by dividing the energy output by the energy intake and expressing the result as a percentage. A flawless procedure would be 100 percent efficient. Real-world processes are never so perfect that they can't be improved upon; thus, the term "efficiency" is used to describe how well we use what we have.
Efficiency may be defined as the ratio of output to input. This means that if you want to know how efficient your process is, you should compare its output with its input. The more output for each unit of input, the more efficient the process is. The input of an process is made up of three parts: fuel, labor, and material. Energy output includes electricity and heat, while input includes gasoline, human labor, and other chemicals.
Why is efficiency important? Efficiency has two main uses in business. First, it's important to determine how much profit a business is making. This requires knowing both how much product it produces and how much energy it uses. Second, efficiency helps reduce pollution. Pollution comes from using too much fuel or energy in production. By using less fuel or energy, we can cut down on the pollution caused by other people's manufacturing processes.
There are two ways to increase efficiency: improve quality or decrease quantity.
Efficiency denotes a peak level of performance in which the fewest number of inputs are used to produce the greatest quantity of output. Reduce the quantity of superfluous resources utilized to create a particular result, including human time and energy. The fewer resources you use the more efficient you are.
Efficiency is a broad concept that can be measured in many different ways. For example, research scientists measure the efficiency of solar cells by calculating how much electricity they convert into heat. Engineers design more efficient cars by making them lighter or using less material; thus requiring fewer efforts to build. As another example, the efficiency of an electric light bulb is calculated from the amount of energy it consumes while giving off light to the amount of energy contained in the battery before it is depleted. The higher the ratio between these two numbers, the more efficient the bulb is.
There are several factors that determine a system's efficiency. One is the quality of materials used in its construction. A highly efficient machine would be one made with high-quality parts that are well designed and manufactured. Other factors include the type of engine or motor used, such as an internal combustion engine versus a battery electric vehicle motor; the size of the engine or motor relative to the load it must drive; and the technology employed to control fuel injection, ignition timing, and air intake filter capacity. Environmental factors such as temperature and humidity also affect engine efficiency.
The efficiency of any machine is determined by how much friction and other variables lower the machine's actual work output from its theoretical maximum. A frictionless machine would be completely efficient. A machine with a 20% efficiency produces just one-fifth of its potential output. A typical motor has an efficiency of around 90%. This means that it produces 9 out of every 10 electrical watts that flow into it from the power source.
Efficiency can be improved through design changes. For example, a more efficient motor uses less energy to do the same job as a less efficient motor. Modern motors are very efficient because they use magnetic fields instead of brushes to connect their coils to the voltage source. This type of motor is called a "electromagnetic" (or "induction") motor. It was first invented in 1821 by Michael Faraday. Before this time, electric motors had mechanical parts that got worn out over time or could break if they were too powerful. The electromagnetic motor does not have these problems; it is also less expensive to produce than previous designs.
Another way to improve motor efficiency is by using inverters. An inverter is a device that can change the direct current (dc) from a battery or generator into alternating current (ac). Most household appliances such as refrigerators and air conditioners run on ac power because this type of wiring is already available in most houses.
Machines are not completely efficient since part of their labor is spent to overcome friction. As a result, work output is never more than work intake. Machine work is measured as "Mechanical Efficiency," which is Work Output divided by Work Input. The maximum possible mechanical efficiency for an engine-driven pump is therefore 1.0.
Efficiency can be improved by using higher quality materials, such as steel instead of iron, cams and bearings instead of chains or belts, and ceramic instead of metal pumps. Mechanical efficiency can also be increased by using lower gear ratios between the motor and the drive shaft, which is important when working from a standing start. Electrical efficiency is not affected by these improvements since electricity is lost in other parts of the system, such as resistance heat loss in the motor and copper losses in the wiring. Electrical power plants are therefore always less efficient than mechanical engines.
Another factor affecting efficiency is the type of fuel used. Hydrogen produces only heat when burned, so it is called a thermal fuel. It is difficult to convert hydrogen into mechanical energy without also producing heat, so it is not useful as a source of power. On the other hand, gasoline produces heat when burned, so it is called a thermal fuel. It is easy to convert its chemical energy into mechanical energy, so it is useful as a source of power.