Other Industrial Engineering & Manufacturing Subjects
Chemical Engineering - Industrial Engineering & Manufacturing
Practice questions to test your knowledge and improve your understanding.
Speisses is a mixture of the following:
Explanation:
Speisses is a specific class of mineral defined by its chemical composition as arsenides and antimonides of heavy metals, primarily containing cobalt, nickel, and iron. These minerals form in hydrothermal environments where arsenic and antimony combine with metallic elements to create distinct crystalline structures. The defining characteristic that makes this the correct classification is the presence of arsenic and antimony bonded to heavy metals, distinguishing it from pure iron-nickel alloys or other mineral groups. Understanding this specific geochemical grouping is essential for identifying ore deposits associated with these heavy metal elements. Therefore, the option specifying arsenides and antimonides of heavy metals accurately describes the fundamental nature of Speisses.
The hardest known natural material is _____.
Explanation:
Diamond is recognized as the hardest known natural material because its carbon atoms are arranged in a rigid three-dimensional crystal lattice. This unique structure creates extremely strong covalent bonds in every direction, making it exceptionally resistant to scratching and deformation. No other naturally occurring substance possesses this specific atomic arrangement that allows it to withstand such immense pressure without breaking. Consequently, diamond is widely used in industrial applications requiring extreme durability, such as cutting tools and drill bits. Its superior hardness distinguishes it from all other minerals found in nature.
Friction factor for fluid flow in pipe does not depend upon the
Explanation:
The friction factor in pipe flow is primarily determined by the Reynolds number, which depends on fluid density, viscosity, and velocity, as well as the relative roughness of the pipe surface. Since the Reynolds number is a ratio of inertial to viscous forces, the physical length of the pipe does not appear in its calculation or the resulting friction factor formula. Consequently, while a longer pipe increases total pressure drop due to cumulative friction, the local friction factor itself remains independent of the pipe's length.
What is the value of included angle of a triangular notch for maximum discharge?
Explanation:
For a triangular notch, the discharge coefficient is not constant but varies with the head of water, making the total discharge dependent on the notch angle. Theoretical analysis and experimental data show that the discharge reaches its maximum value when the included angle is exactly 90 degrees. At this specific angle, the balance between the width of the notch and the velocity distribution optimizes the flow rate. Consequently, a 90-degree triangular notch is the standard design for achieving the highest possible discharge in such weirs.
Adding bile to triglycerides _______.
Explanation:
Bile acts as an emulsifying agent that breaks large fat globules into tiny droplets without undergoing a chemical reaction itself. This physical process dramatically increases the total surface area available for digestive enzymes to act upon. By creating more interface between the fat and water, bile allows lipases to efficiently access and break down triglycerides. This mechanical dispersion is essential for effective lipid digestion in the small intestine. Therefore, the primary function is increasing surface area rather than chemical modification or digestion.
For separating small pieces of metal from engine oil of a car, the best separating technique is the
Explanation:
Filtration is the ideal technique because it physically separates solid metal particles from the liquid engine oil using a porous barrier. This process allows the fluid to pass through while trapping the larger solid debris, effectively cleaning the oil without altering its chemical composition. Unlike distillation or evaporation, which rely on boiling points and are unsuitable for this mixture, filtration directly addresses the solid-liquid separation needed here. It is a simple, efficient, and standard method widely used in automotive maintenance to protect engine components from wear.
Fog is an example of colloidal system of
Explanation:
Fog consists of tiny liquid water droplets suspended within air, which is a gas phase. This specific arrangement defines a colloidal system where the dispersed phase is liquid and the dispersion medium is gas, scientifically known as an aerosol. Unlike clouds that may contain ice crystals, fog is strictly liquid-in-gas, making option A the accurate description of its physical state. Understanding this distinction helps clarify how atmospheric phenomena function as colloids.
Auto collimator is used to check
Explanation:
An auto collimator is an optical instrument designed to project a precise reference beam that allows for the accurate measurement of angular deviations. It works by reflecting light off a mirror or surface, where the displacement of the reflected image directly indicates the specific angle of tilt or misalignment. This capability makes it the essential tool for verifying the angular accuracy of machine tools, optical axes, and precision instruments. Consequently, its primary function is strictly dedicated to checking angles rather than surface properties like flatness or roughness.
On oscilloscope screen for dynamic measurement, lissajous diagram is normally used to determine the __________ of the input signal.
Explanation:
A Lissajous diagram is generated by applying an unknown signal to the vertical input and a reference signal of known frequency to the horizontal input of an oscilloscope. By observing the resulting pattern, one can determine the frequency ratio between the two signals, allowing the calculation of the unknown frequency. This method relies on the relationship between the number of tangencies and the frequency ratio, making it the standard technique for frequency measurement using this specific display mode.
Which one of the following is incombustible?
Explanation:
Carbon tetrachloride (CCl4) is incombustible because its molecular structure consists entirely of carbon and highly electronegative chlorine atoms, which suppress the combustion reaction rather than support it. Unlike hydrogen or carbon-based fuels like acetylene that release energy when reacting with oxygen, CCl4 acts as a fire suppressant by absorbing heat and forming a protective layer over the burning material. This unique chemical property prevents the oxidation process necessary for fire, making it safe to use in specific fire extinguishing scenarios despite its toxicity.
The temperature at which ferromagnetic material can no longer be magnetised by the outside forces, is termed as the
Explanation:
Ferromagnetic materials possess a unique property where their atomic magnetic moments are aligned in parallel domains, creating a strong net magnetization. As temperature increases, thermal agitation disrupts this orderly alignment, weakening the magnetic strength. At a specific critical threshold known as the Curie temperature, this thermal energy completely overcomes the internal exchange forces holding the moments together. Consequently, the material undergoes a phase transition from a ferromagnetic state to a paramagnetic state, losing its ability to be permanently magnetized by external fields. This precise point of magnetic disorder is exclusively defined as the Curie temperature in physics.
The element in this list with chemical properties similar to magnesium is ________.
Explanation:
Magnesium and Strontium both belong to Group 2 of the periodic table, known as the alkaline earth metals. Elements within the same group share the same number of valence electrons, which directly determines their chemical behavior and reactivity. Because Strontium has the same electron configuration in its outer shell as Magnesium, it exhibits nearly identical chemical properties, such as forming +2 ions and reacting similarly with water or oxygen. This vertical relationship in the periodic table ensures that Strontium is the element with the most similar characteristics to Magnesium among the choices provided.
Maltose is a _______.
Explanation:
Maltose is formed when two glucose molecules link together via a glycosidic bond, which defines it as a disaccharide. Unlike monosaccharides that exist as single sugar units or complex starches made of long chains, maltose represents a specific intermediate sugar found in germinating grains. This dual-unit structure allows it to be easily broken down by enzymes into simple glucose for energy. Therefore, its classification relies entirely on being composed of exactly two monosaccharide units. This chemical composition makes the disaccharide label the only accurate description among the choices.
The scientific method begins by making _________ about the world around us.
Explanation:
The scientific method fundamentally starts with making observations about the natural world to gather initial data and identify phenomena. These observations serve as the essential foundation upon which researchers build hypotheses and design experiments. By carefully noting details and patterns in our environment, scientists ensure their inquiry is grounded in real-world evidence rather than assumptions. This initial step allows for the systematic collection of information needed to ask meaningful questions and explore cause-and-effect relationships later. Without accurate observations, the entire scientific process would lack the necessary starting point for logical deduction and discovery.
In troposphere (the weather domain), the temperature ‘t’ at height ‘h’ above the sea level in metres is given by (where, temperature at sea level is 15°C and t is in °C.)
Explanation:
In the troposphere, temperature decreases as altitude increases, a phenomenon known as the environmental lapse rate. The standard rate is approximately 6.5°C per kilometer, which converts to 0.0065°C per meter. Since the base temperature at sea level is 15°C, we must subtract the product of this rate and height from the initial value. Therefore, the correct formula represents the starting temperature minus the temperature drop proportional to the height above sea level.
Larger length & diameter water pipes are made by
Explanation:
Semi-centrifugal casting utilizes a rotating mold to generate centrifugal force, which effectively pushes molten metal against the mold walls. This process is ideal for creating large-diameter pipes with uniform wall thickness and high structural integrity. The rotational speed ensures that impurities are forced to the center while the solidified metal forms a dense outer layer. Consequently, this method is the standard industrial technique for producing large water pipes that require consistent quality and strength.
The softness or hardness of a grinding wheel depends upon the type & amount of bonding material used. For general purpose cutter grinding __________ grinding wheel is normally used.
Explanation:
Aluminium oxide wheels are the standard choice for general-purpose cutter grinding because they offer a balanced combination of strength and durability. These wheels feature a harder abrasive grain compared to silicon carbide, making them ideal for grinding tough materials like steel and cast iron. The bonding material is selected to provide a moderate hardness that allows for efficient material removal without excessive wear. This specific type of wheel ensures a smooth finish while maintaining the structural integrity required for various cutting operations. Consequently, it is the preferred option for most industrial applications where versatility is key.
Glycerophospholipids can interact both with other lipids and water because they contain ________.
Explanation:
Glycerophospholipids are amphipathic molecules that possess both hydrophilic polar heads and hydrophobic nonpolar fatty acid tails. This dual nature allows the polar regions to form hydrogen bonds with water molecules while the nonpolar regions interact via hydrophobic forces with other lipid tails. Consequently, this specific structural arrangement enables them to spontaneously organize into bilayers and micelles, which are fundamental to forming stable cell membranes in aqueous environments.
Fire refining process is employed in case of
Explanation:
Fire refining, also known as the Parkes process, is a specific metallurgical technique primarily utilized for the purification of copper. This method relies on the unique property of adding a small amount of zinc to molten copper, which selectively reacts with and removes impurities like silver and gold. The process involves heating the copper in a reverberatory furnace to create a slag layer that captures these valuable byproducts, leaving behind high-purity copper. Consequently, this technique is exclusively associated with copper refining among the given options.
Carbide tipped cutting tools are manufactured by powder metallurgy techniques and have a composition of
Explanation:
Carbide-tipped cutting tools are primarily composed of tungsten carbide, a super-hard material formed by combining tungsten and carbon, which provides exceptional wear resistance for machining operations. To enhance toughness and prevent the brittle carbide from shattering under impact, a small percentage of cobalt is added as a metallic binder that holds the hard particles together. This specific microstructure, typically consisting of about 90% tungsten carbide and 10% cobalt, allows the tool to maintain a sharp cutting edge while withstanding the high pressures and friction generated during metal cutting. The manufacturing process utilizes powder metallurgy to sinter these components into a dense, durable insert that outperforms standard high-speed steel tools. Consequently, this precise composition is the defining characteristic of modern carbide cutting tools used in industrial applications.
Chromium molybdenum steel can not be welded using __________ welding.
Explanation:
Chromium molybdenum steels are susceptible to hydrogen-induced cracking during the welding process, which makes them unsuitable for electrical resistance welding due to the intense localized heat and rapid cooling rates. This specific welding method generates high temperatures that can compromise the material's microstructure and lead to brittle failures in these alloy steels. Consequently, electrical resistance welding is avoided to prevent structural defects and ensure the integrity of the welded joint.
Baffles provided on the shell side of a shell and tube heat exchanger are meant for
Explanation:
Baffles are strategically placed on the shell side to serve a dual purpose: they mechanically support the tube bundle to prevent sagging and vibration, while simultaneously directing the shell-side fluid flow across the tubes. This cross-flow arrangement significantly increases the fluid velocity and turbulence, which enhances the heat transfer coefficient and prevents the formation of stagnant zones where fouling could occur. By forcing the fluid to change direction repeatedly, baffles effectively minimize the risk of tube erosion and deposit accumulation, ensuring efficient and long-lasting heat exchanger operation.
Tin based white metals are used, where bearings are subjected to
Explanation:
Tin-based white metals, also known as Babbitt metals, possess a unique soft matrix structure that allows them to embed abrasive particles and conform to shaft irregularities. This self-adjusting capability is specifically designed to handle extremely high loads and pressures by distributing stress over a larger area, preventing immediate failure. While their softness makes them unsuitable for high-speed or high-temperature environments, their primary strength lies in supporting heavy static or dynamic loads where other materials would deform or wear out too quickly.
All of the following alloying elements of steel increases hardness but sacrifice ductility, except
Explanation:
Nickel is unique among common steel alloying elements because it primarily enhances toughness and ductility rather than sacrificing them for increased hardness. While elements like chromium, vanadium, and molybdenum form hard carbides that significantly increase strength and hardness at the expense of ductility, nickel acts as an austenite stabilizer that improves the material's ability to deform without fracturing. Consequently, adding nickel allows steel to maintain or even improve its ductile properties while providing other beneficial characteristics like low-temperature toughness, making it the exception in the context of elements that strictly trade ductility for hardness.
The volume in the pump when the pump piston is all the way down represents the _______.
Explanation:
When the pump piston is fully depressed, it mimics the heart's ventricle at the end of a contraction, squeezing out as much blood as possible. This specific remaining volume inside the chamber is defined as the end systolic volume, representing the minimum amount of blood left after a heartbeat. The concept directly correlates the mechanical position of the piston to the physiological state of the heart muscle finishing its pumping action. Therefore, this volume measurement accurately identifies the residual blood quantity remaining in the system after maximum ejection.
The greatest expression of the lac operon occurs when lactose levels are _____.
Explanation:
The lac operon is maximally expressed only when lactose is present to inactivate the repressor and glucose levels are low. When glucose is scarce, cellular cAMP levels rise, allowing cAMP-CAP to bind DNA and strongly stimulate transcription. Conversely, high glucose concentrations trigger catabolite repression, which prevents the transport of lactose into the cell and shuts down operon expression. Therefore, the condition for the greatest expression is specifically when glucose is low, making the statement about high glucose preventing transport the accurate description of the regulatory mechanism.