Mechanical Engineering

hardness is defined as a resistance to plastic deformation or penatration.Hardness is defined as the ease with which hardness may be attained by quenching . It is also defined as the ability to develop maximum hardness by quenching.It is the process to have a hardened layer of marten site after quenching and also to have high hardness at same given depth.

The material which having low critical cooling rate have high hardenability.The factors which reduce critical cooling rate increase the hardenability.alloy steels have low critical temperature.

In plain carbon steels are contain not more than .5% of silicon and 1.5% of manganese.These steels are strong,tough,ductile and used in expensive materials.Increase in hardness and strength in plain carbon steel is depend upon the presence of carbon content.

Bo dang di hoi, deo biet

travel jack hydraulic type with 50 metric tonnes capacity - specification

Pros : Readily available, Easy to shape, Weldable, Many shapes available

Cons : Not that strong for its weight, rusts easily, cannot be made better by heat treatment

It depends on the type of stainless steel you are referring to. Austenite and ferritic stainless is not heat treatable in which case carbon steel could be made far harder. However..martensitic stainless steels are heat treatable in which case they could be made harder depending on the alloy contents. Generally the more carbon a steel contains, the harder it can be made. Chromium; a key ingrediant in stainless steels, can also increase hardenability.

that doesnt make any sense retard

He is not all that retarded;

I have an 8 horsepower Honda engine

Clearly written it says 242 CC

My calculations would indicate there are:30.25 cc to make one horse power

At least with a Honda engine.

Of course the compression ratio would change that figure.

Also the octane of the gas would also have a bearing.

Generally after I have calculated a few engines.

My answer would be approximately, 30 cc to one horsepower.

By the way,, "doesn't" is spelled with an apostrophe.

IslandNick

Rectifiers will not give a smooth DC voltage. There are ripples in the voltage given the rectifier. So in order to smoothen the voltage we use capacitor in parallel to the rectifier output.

Now lets see how the capacitor smoothen the voltage that is coming from a rectifier......

Capacitor blocks DC and allows AC......

If we take the voltage that is coming from the rectifier it has some ripples

in addition to DC, these ripples can be divided in to sinusoidal wave forms

( fictitious )according to the Fourier series. So the rippled DC now divided

( fictitious ) in to a pure DC and sinusoidal AC wave forms having the frequency that is multiples of ripple frequency.

Now the DC current will not pass through the capacitor as the capacitor blocks DC. But the AC will pass through it i.e the ripple wave forms that are divided ( fictitious ) in to sinusoidal AC wave forms will pass through the capacitor. So only DC current enters in to the load, which will produce a pure DC voltage drop across the load.

In this manner the capacitor smoothens the voltage.

Using the usual Jet A1 its a combination of factors including that piercing nose, the raked wings to reduce drag, the pencil thin body for least resistance but most of all those afterburners. Look up the Olympus 593 Mrk610 turbojet engines and say hello to power!

Compound pulleys are used in a similar manner to a gearbox. You can select the ratio to suit the load and the power source. With the correct pulley combination one man can lift 10 tons from a truck onto a ship without motorised assistance.

Potential Elastic Energy.

Net Positive Suction Head. It is the difference between hydraulic pressure and vapor pressure, usually of concern at the inlet of a pump. Without sufficienty high NPSH at a pump inlet, there will be cavitation in the pump. Within a centrifugal pump there can be pressures lower than at the inlet as the fluid is moved by the impeller. If any of those pressures is lower than the vapor pressure, vapor pockets- bubbles- form and you get cavitation. A more complete explanation: http://en.wikipedia.org/wiki/NPSH

"Nothing is true, everything can be questioned" but while learning the basics one should not question :(

It takes an engineer to undertake the training of an engineer and not, as often happens, a theoretical engineer who is clever on a blackboard with mathematical formulae but useless as far as production is concerned ;)

yes of course

If you are training in the UK, visit the City and Guilds' website -there you will find everything you need to know about the curriculum for electrical training.

Planning is similar in all applications. That's when you decide how and what to do and in which order.

I assume you mean PLANING. That's the process of making a surface flat.

In a tensile test, a specimen of material is pulled apart slowly until it breaks. Measurement is continuously taken of the increase in length and the force applied. The increase in length is normalized by dividing it by the original length, and the force is converted to stress by dividing it by the original cross-section area of the specimen. The results are plotted on a graph, called a stress-strain curve, with the stress on the Y axis and the strain on the X axis. The initial part of the curve is usually linear. That linear section is called the elastic region. The slope of the line in that area, which is stress divided by strain in the elastic region, is the elastic modulus.

What are the disadvantages on diesel? Please may i have information Thankyou Jasmine Mottram
Parts can be somewhat harder to get and generally more expensive. They generally have a tendency to smoke more under heavy acceleration. Almost all of them are known to blow head gaskets. harder to start in cold weather. Sluggish acceleration if you don't got a turbo.

Yes, a trolley is considered a second class lever. A hammer is considered a third class lever. Also, a clothes pin is considered a third class lever.

That really depends on the type of stainless steel and how it is conditioned. For example 300 series steels that are annealed have a yield strength of 30,000 psi and a tensile strength of 80,000 psi. But if cold worked these increase to 65,000 psi and 125,000 psi, respectively, and even higher depending on method. For high strength stainless steels such as A286 or 17-4 PH, tensile strengths over 160,000 psi are realized.

Yes. An arch bridge is one of the more efficient ways of building and maintaining a bridge. Beam bridges are not as efficient. For a given span and height, an arch bridge will carry a greater load using less material. The beam structures of a beam bridge can be constructed of wood, reinforced concrete or steel (in increasing order of strength). The beams, however, must be supported by piers or an abutment at each end, which can be made out of concrete, masonry, stone, or steel (or combination thereof). The arch structure of an arch bridge can be constructed of wood, reinforced concrete, steel, or masonry, and the arch can be supported by abutments as described above, or the arch can extended down to the foundation itself. The primary advantage of an arch is that stresses caused by the load on the bridge are converted primarily into compressive stresses that are carried along the arch into the ground. Materials like stone, masonry and concrete are particularly good at carrying these compressive stresses. In contrast, loads on a typical beam-type bridge creates large tensile stresses on the bottom of the beams. Since stone, masonry and unreinforced concrete have very little capacity to withstand tension, none of these materials can be used to make a reliable and efficient beam-type bridge of any significant span.