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In Mechanics

It reduces the amount of friction between the parts of the machine and keeps it cool, preventing it from over-heating and causing damage to the machine as well as allowing it …to work faster and easier. (MORE)

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In Physics

Mechanical Advantage is the number of times a machine increases the input force. Efficiency is the ratio of output work to input work.

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In Uncategorized

Evaporation of sweat from the skin surface has a cooling effect due to the latent heat of evaporation of water.

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In Physics

The mechanical efficiency can't be over 100% because a type of energy is always lost. For example, it can be lost as heat, sound or even light. When you use a light bulb, it p…roduces light, but heat is lost in the process. See what I mean! In most cases, heat is lost due to friction. the work put out by a machine is always less than the work put into a machine to do the work. Therefore no machine is 100% efficient. As well.... Efficiency is (power out/power in) x 100. To get an efficiency of *more* than 100%, the machine must give more power out than is put in. No machine has ever been demonstrated that does this, and until someone can show this result (power out *more* than power in), we know that any machine has an efficiency less than 100%. (MORE)

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A mechanism is a system of moving parts that changes an input motion and force into a desired output motion and force. These are hidden in most machines.

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In Uncategorized

the 5s because it has better service but it dosent have diffrent colrs just silver gold and black

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If the generator produces 240v at 25 amps, this amounts to 6000 watts, so if the losses are 900 watts, the total power generated must be 6900 watts. The efficiency is then 600…0/6900 = 0.87, or 87 percent. You have not put in heat losses however, or are they included in 'mechanical? ****The previous answer above is incorrect. Read and understand the question first. The general rule of thumb when calculating power equations is to factor in power loss as an inclusive amount of the total power being generated. unless stated otherwise Therefore 240v at 25amps gives 6000watts power loss is 900watts The question says that the power the generator produces is 240v at 25amps which is not the useful power it delivers ( this is a very common mistake in learning and real life applications) and that is why we do not add power loss to the total power generated, rather we subtract power loss from the total power generated. Efficiency of the generator is actually the power the generator is delivering for useful work compared to the total power generated. In this case 6000 watts (Total power produced) - 900watts ( power loss) = 5100watts Therefore the geneator's efficiency is 5100/6000 x 100% = 85% For the last part of the previous answer, For a generator, mechanical movement is counter reacted by friction which produces heat and noise while resistance to electrical current flow and electomagnetic induction generate heat. Of course this is just a general description, it gets quite complicated in advanced level analysis where back e.m.f, magnetic resonance, physical construction (generator type) and purity of construction materials just to mension a few are involved. I'm only a simple physicist, but I feel the word 'produced' is ambiguous, and I took it to mean the same as 'delivered'. If I went out and bought a small generator, and the sales people said it was a 2 Kw generator, I would expect it to deliver 2 Kw, and not 85 percent of that figure. So I think you could take this either way. To use the word 'produced' is not ideal, better to use 'generated power' and 'output power'. (MORE)

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In Science

power in equals power output plus power loss so input power for this question is 100 kw now use efficiency formula 100/80 times 100 to get 80% efficient

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20c + 5 = 5c + 65 Divide through by 5: 4c + 1 = c + 13 Subtract c from both sides: 3c + 1 = 13 Subtract 1 from both sides: 3c = 12 Divide both sides by 3: c = 4

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In Bicycles

A properly maintained bicycle - like any machine - will have less unwanted friction and higher efficiency.