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Engineering
Engineering is an art and profession devoted to designing, constructing, and operating the structures, machines, and other devices of industry and everyday life.
5,839 Questions
A Hydraform wall is a wall that is built using the Hydraform building blocks. Hydraform blocks are interlocking building blocks that is produced using a Hydraform block machine. Hydraform block machines utilises compressed earth method in creating building blocks, soil and cement is mixed and then compressed using the machine to manufacture high quality stabilised building blocks. Blocks are intelocking and require up to 70% less mortar than conventional bricks or blocks.
What is the fifth and 9fifth percentiles?
The 50th percentile is average. The 5th is way below and the 95th is way above.
The 5th and 95th percentiles are the lines that set of the "edges of the curve" in a distribution over a bell curve. If you draw the bell, and mark the 5th and 95th percentile spots, those marks separate the bulk of the curve from its edges. The 5th percentile sets off the bottom edge and the 95th percentile sets off the top edge of the curve.How much water is in a square of 1 foot?
A square foot cannot hold water its 2 dimensional. What you see is what you get .
A one cubic foot container can hold 7.48 US gallons of liquid.
How do magnetic drive pumps work?
In a normal (centrifugal) pump you'd have a motor turning a shaft, then the shaft going through into an enclosed space where the pump wheel/impeller/rotor would sit.
It's a simple enough design, but it relies on a good seal where the axle passes from the pump housing to the motor.
And creating that seal can be difficult. It needs to be tight enough not to leak while still allow the axle to turn freely. It should last for ages too. Tricky.
"Magnetic drive" for pumps refers to that instead of having a drive shaft going through the pump housing to the motor, what connects the pump to the motor is a powerful magnetic field. This field acts straight through the wall of the pump housing.
Basically there's one magnet stuck to the pump wheel/impeller/rotor and another to the spinning end of the motor. And just like you can "magically" move a magnetic object on top of a table by moving another magnet underneath the table, the pump wheel will spin with the motor, even though there's no material connection between them.
This lets you use a fully enclosed pump housing w/o any axle seals that can wear out and leak. Quite clever.
What is the principle of fluid bed dryer?
Fluid bed dryer works on a principle of fluidization of the materials.
In fluidization process, hot air or gas flow is introduced through the bed of solid particulates.
This hot air will move upwards through the spaces between the particles and remove the moisture.
Why do tires have less friction when it rains?
Because the water on the ground acts like an oil diminishing the grip. And when the ground is wet the water molecules resides between the ground and tires so, the tire is not in total contact with the ground.
How do you design an adsorption experiment of colour on adsorbent?
put the beads in bacterial liquid culture for some day for adsorption. check the coating by
conducting SEM surface topology.
What is standard purchase specifications?
Standard purchase specifications define the various characteristics of an item that is to be purchased. It also specifies the quantity of the item to be purchased.
What are indigo dyes and how are they made?
Indigo is a distince blue color, and the dyes have a long history of manufacture and use. Certainly there are synthetically manufactured today as opposed to being made with Indigo tinctoria and I. suifruticosa and other legumes as they were "back in the day" when they were first being used. Links are provided to a couple of articles posted by our friends at Wikipedia, where knowledge is free.
sudo apt-get install python-parallel
sudo rmmod lp
log out
sudo modprobe ppdev
python
import parallel
prPrt = parallel.Parallel()
prPrt.setData(0x01)
How can a wings lift be increased?
Lift can be increased by curving the wing downward. Most aircraft have 'flaps' at the rear inner edge of the wing to achieve this. Some aircraft even have 'slats' at the front of the wing to increase lift even more. - If you google 'aircraft slats', you will see a great picture of slats and flaps on an Airbus A310
What is Batch Production and an example of how CAD CAM can aid this?
Batch production is the process of producing a set quantity of a set component, so not where you need 15,000 of a component, but a smaller set. This is desimilar to singular components which are better off produced by hand or a production line which is an ongoing process.
Cad Cam can be used to quickly produce a design brief for a batch product, saving both time and monies.
What are facts about the Van de Graaff generator?
They are used to make peoples hair stand up on their head.
Why phase modulation is least used?
Actually phase modulation was used for the color signal in all analog TV systems.
Phase modulation, with some signal preprocessing, was used to indirectly get frequency modulation in many FM transmitters.
Certain modems use phase amplitude modulation.
etc.
What is the mathematical definition for double implication?
In order for you to read mathematical text accurately, you must know what we mean when we see or write factual implications. Compare the two sentences from ordinary talk:
. . . . . 1. If it stops raining, [then] I'll go to the market.
. . . . . 2. If I win the lottery, [then] I'll buy a new car.
The two sentences have parallel structure (If A, then B), but the usual meaning is quite different. In #1, the inference one picks up is that if it does not stop raining, I won't go to the market. In #2, on the other hand, the failure to win the lottery is hardly grounds for keeping the old car; I might decide to buy a new car on credit, for instance.
Many assertions in math books are of the form "If A, then B". Mathematics is hard enough without ambiguous statements! Which of the two statements above is giving the correct, agreed mathematical usage?It's #2. We'll come back to these examples later.We often write A ==> B for "if A, then B". This means only that A implies B (B is a consequence of A, as the arrow suggests). Use common sense to see that this is equivalent to its contrapositive, not B ==> not A (for if you did get A, ...).
. . . . . Statement: If two numbers are odd, then their sum is even.
. . . . . Contrapositive: If the sum of two numbers is odd, then at least one of them must be even.
This is logically different from the inverse, not A ==> not B, and its contrapositive, B ==> A (the converse of A ==> B). Continuing the above example:
. . . . . Inverse: If (at least) one of two numbers is even, then their sum is odd
which you can see is false.
The inverse (and converse) are saying that you can't have B without A, which can be rephrased (even in common parlance) as B only if A:
. . . . . You'll get the flu only if you are exposed to an influenza virus.
The converse of this statement is false; otherwise we'd all be ill! In particular, the correct mathematical rendition of the connoted meaning of #1 is:
(*). . . . . I will go to the market if and only if it stops raining.
When we state an implication in mathematics, it contains no information about the converse (or equivalently, the inverse) statement.
Combining the two implications, A ==> B and B ==> A, we write B <==> A or A <==> B (B if and only if A); the assertions A and B carry the same actual information, i.e., are equivalent.
In mathematics, it was decided that "or" is non-exclusive. That is, when we say that A or B holds, we mean that at least one (so possibly both A and B -- we do not exclude that) of the two statements are true.
A counterexample to an assertion is an example that shows that the assertion is false. For instance, here's a stupid statement to ponder:
. . . . ."Every real number is a rational number (usual fraction a/b, with a and b integers, and bnon-zero)."
Come on! you might say. \pi is not rational! That is correct: \pi is a counterexample to (example against) the assertion.
In mathematics, statements are to be proved true, or shown to be false by finding a counterexample. That's right, just one. But often enough, once you've found one counterexample, there are many more.
For emphasis, I remind you that no incomplete list of examples suffices, of itself, to prove that a mathematical statement is true; it only says that you haven't yet found a counterexample!
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The following questions will be part of the first homework assignment, and they are to be submitted as WIproblems.
(There is no reason why you should be able to do these problems quickly, but you can do them if you persist.)
. . . . . 1. The context here is pairs of whole numbers [integers]. In each case,
. . . a) determine whether A ==> B, and whether B ==> A.
. . . b) write the outcome in one sentence, using one of the following: if, only if, if and only if, neither implies the other, as in (*).
i) A: Both numbers are even numbers. . . . B: Their sum is even.
ii) A: Both numbers are odd numbers. . . . B: Their product is odd.
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. . . . . 2. Carry out (a) and (b) in #1 for the following assertions about functions f(x):
i) A: f(x) is a polynomial function; . . . B: f'(x) (the derivative of f(x)) is a polynomial function.
ii) A: f(x) is a rational function; . . . B: f'(x)(the derivative of f(x)) is a rational function.
(A rational function is a function that can be written in the form f(x) = p(x)/q(x), where p(x) and q(x) are polynomials. That is how one writes the general rational function.
You may freely use the algebraic facts about polynomials.)
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Steven ZuckerWhat will increase when you increase pitch angle rotor blades?
A: The pitch angle is a speed factor and also a torque factor. Increasing or decreasing the angle will effect these factors inversely
Since we know by conservation of energy that no machine can output more energy than was put into it, the ideal case is represented by a machine in which the output energy is equal to the input energy. For simple geometries in which the forces are in the direction of the motion, we can characterize the ideal machine in terms of the work done as follows: Ideal Machine: Energy input = Energy output
Work input = Fedinput = Frdoutput = Work output From this perspective it becomes evident that a simple machine may multiply force. That is, a small input force can accomplish a task requiring a large output force. But the constraint is that the small input force must be exerted through a larger distance so that the work input is equal to the work output. You are trading a small force acting through a large distance for a large force acting through a small distance. This is the nature of all the simple machines above as they are shown. Of course it is also possible to trade a large input force through a small distance for a small output force acting through a large distance. This is also useful if what you want to achieve is a higher velocity. Many machines operate in this way. The expressions for the ideal mechanical advantages of these simple machines were obtained by determining what forces are required to produce equilibrium, since to move the machine in the desired direction you must first produce equilibrium and then add to the input force to cause motion. Both forceequilibrium and torque equilibrium are applied.
