what reduces the efficiency of a machine?

Answer 1

Simple machines: Generally friction. In engines a big loss (which is very common) is the loss of potential energy found in, say, a gallon of gasoline by all that wasted heat in the engine compartment - which is doing nothing productive. Heating a house: Any heat which goes up the chimney is a sign of inefficiency. If a tennis ball were 100% elastic it would be 100% efficient: Drop it once and it would bounce forever. But it's not perfectly elastic, the surface upon which you drop it absorbs some energy, you hear it hit the floor (sound energy... wasted energy), you know there is air friction.....

Answer 2

Well, you dont ask for "much" do you? LOL! Ok, friction "does" reduce the efficiency of a machine because it creates heat, and the machine has to "get rid" of it, and it slows down a machine. The only "good thing" that is associated with friction is on a 'brake pad'! Then you want all the friction you can get as it will "stop" you. Where you get an "ax" as an example of a "wheel and axle" is beyond me. An Ax is a wedge, that is simply driven into lumber to devide it. Energy, when the work is done, is stopped. If there is no "work" being performed, there is no energy output. Energy is the result of some "force" being applied in a direction for locomotion or performance. Given enough "power", work can be done more efficiently so that time is saved. The more power you have for a "saw" to work, the higher the performance and the greater efficency that it will "work" so that time and energy is kept to a maximum performance and shortened. The six types of machines.... (1) Screw - Helical screw for lifting water (2) Wedge - Devides wood when driven into it. (3) Incline plane - makes rolling something easier than lifting it. (4) Pulley - Able to lift great weights, wtih the more pulleys you have. (5) Lever - Archemedies said "Give me a large enough lever, and a place to stand, and I can move the World". (6) Fulcrum - Place for the lever to rest, so that it can move that world. I wish you well... Jesse

Answer 3

Efficiency of a machine is the ratio of output energy to input energy. It is usually expressed as a percentage therefore:

efficiency=(output energy)/(input energy)*100

The output energy is never equal to the input energy in machines because some amount of energy is always lost by heat due to moving parts.

Therefore the answer to your question is losses. The efficiency of machines are reduced due to losses.

Examples:

An engine. The combustion of the fuel causes movement of the engine. Through friction of moving parts heat is lost. Also not all the energy from the combustion is use for movement or lost by friction but goes out of the engine as exhaust. In power plants for example where they use large engines or turbines that produces lots of exhaust or heat (waste energy). The "waste energy" is used for other processes in near by plants or on that same plant. Example heat of water for whatever. Doing this the efficiency of that engine increases because you can get more out of what you put in.

An electric motor. You start-up a motor. The electrical energy at the terminals of the motor is not the same on the shaft of the motor. Energy is lost by heat of the current in the copper wire of the motor coils and the motor core which produces the magnetic field. Energy is also lost by friction of the motor assembly rotating.

Electrical machines are usually more efficient than mechanical machines because they have less losses.

Answer 4

Energy efficiency is the amount of useful energy extracted from a system divided by the total energy put into a system. It may also be thought of as the efficiency with which we are capable of utilizing a resource. If we don't use the energy released from the chemical bonds in a resource, the energy goes into waste heat, sound, thermal vibrations, or light. The more energy conversion steps there are in a process, the more energy you lose as waste heat. For example, in order to run your car, the chemical potential energy in the gas must first be converted into thermal energy (or heat energy) by igniting the fuel. The thermal energy is converted to mechanical energy to make the engine run. This three step process has an overall maximum efficiency of about 30%. That means that 70% of the energy initially stored in the gasoline was lost as waste heat, mostly in the form of thermal vibrations to the surrounding materials. This illustrates the importance of learning about energy and trying to find better ways to responsibly use the resources available to us.

Answer 5

The environmentalist have modified the combustion engine. #1 they reduced the chamber temperature to reduce the CO2 produced. As CO2 is reduced u don't get the miles per gallon. The reduced temperature also reduces NO2 ,which is photo chemical smog. which is also a fertilizer that is produced by nature by lightning. It dissolves in water.

Answer 6

All types of resistance would cause a decrease in efficiency.

Answer 7

Usually friction.

Answer 8

Friction, accuracy and consistency