The key issue in making steel is reducing the carbon content. Answer : hotter. These, in turn, could be inserted into holes drilled by miners or railroad workers steam chamber for bending wood ltd blast apart rocks. In California, oaks are affected by the fungal disease foamy bark canker. Thus began intense competition to spread the telegraph throughout the United States. In England, oaks have been a national symbol since at least the sixteenth century, often used by Shakespeare lhd convey heritage and power.

Two Conductors Parallel Speaker Wire. OEM Service. Double Jacket Fire Hose. Solid Color Polos. Woman's Camisole ladies sports camisole. Stock Apparel. Bamboo bathrobe. Islamic Sweatshirt ILM. Recommendations for you. Women garments stock Top X0AW Drizabone Belltrees Vest-Heavyweight.

Robes de Soire S Strain Relief Boots. Bamboo fiber clothing series. Dora Kid's Skirt. Clothing RZ-DX Answer : Under same flow conditions the friction head loss increases as the size change to the 4. Answer : At constant head, capacity is proportional to d Answer : At constant capacity, head is proportional to. Answer : At constant diameter, head is proportional to flow 2. Give Some Properties Of Errors? Answer : Errors give the difference between the measured-value and the true value Accuracy of a measurement system is measured in terms of error A study of error helps in finding the reliability of the results.

Define The Term Contraction Coefficient? Answer : The ratio of area of jet contracted and the cross section of the orifice. What For Pycnometer Is Used? Answer : Pycnometer is used to measure specific gravity of the liquid. Answer : Fine wire strain gauge Metal foil strain gauge Piezoresistive gauge. Answer : Primary sensing element Variable conversion or transducer element Variable manipulation element Data transmission element Data processing element Data presentation element Data storage and playback element.

Answer : Sensing and converting the input to a convenient and practicable form. Presenting the processed measured variable in quantitative form. Answer : A pelton wheel is broken by a nozzle directing a jet on the back of the buckets.

What Is Static Pressure? How Is It Measured? Answer : The pressure caused on the walls of a pipe due to a fluid at rest inside the pipe or due to the flow of a fluid parallel to walls of the pipe is called static pressure. This static pressure is measured by inserting a pressure measuring tube into the pipe carrying the fluid so that the tube is at right angle to the fluid flow path. Answer : Stability, accuracy and speed of response are the three requirements of control system.

Answer : Any obstruction of a streamflow over which water flows is weir. When the downstream water level rises over the weir crest, it is called submerged weir. Answer : Spillway is an essential part of a large dam and provides an efficient and safe means of releasing flood water that exceeds the design capacity of the reservoir.

Siphon spillway is spillway designed to discharge water in a closed conduit under negative pressure. Answer : Culverts are built at the points of lowest valley to pass water across the embankments of highways or railroads.

Stilling basin is transitional energy dissipating structure to avoid the damaging process by a highly accelerated spilled water. Standpipe is used principally for alleviating the transient pressures in large pipeline system. It also works as a pressure relief valve for the upstream pipe during the turbine shut off. Answer : A scheme in which the discharge is varying and only that much water can be utilised for conversion as available in the river.

Answer : The approximate constant and continuous power which is assured at power station and would be available throughout the year is called firm power. Answer : The economic diameter of a power tunnel is determined such that the total value of following two factors is least. Answer : The three functions served by a surge tank are.

Answer : The economic diameter of a penstock required to carry a discharge is the one at which annual costs due to the greater investment do not exceed the annual value of resulting increment energy output.

Answer : In anti-friction bearings rolling components are introduced between the sliding surfaces. In hydrostatic bearings lubricant is supplied at a high pressure to a pocket in the bearing. What Is Inviscid Fluid? Answer : The ratio of change of momentum of a mass of fluid is equal to the vector sum of all external forces acting on it.

Define Turbulent Flow? Answer : Flow in which adjacent layers mix continuously, so that the flow pattern is unsteady, full of eddies, and apparently without any mathematically expressible regularity.

Define Reynolds Law Of Similitude? Answer : Two geometrically similar flow systems subject only to friction and inertia Pigment Stain For Wood Youtube forces are dynamically similar if both have the same 'Reynolds' number. Answer : In boundary lubrication condition the ratio of thickness of lubrication film to surface roughness CLA value is less than 1 and for fluid film lubrication condition this ratio is greater than 5 and less than Answer : The order of the system is the order of the highest derivative of the ordinary differential equation with constant coefficients which defines the system mathematically.

What Is Bode Plot? Answer : Bode plot is a logarithmic plot used to represent transfer functions. The Bode plot consists of two plots namely. Answer : If a number of measurements are made on same true value, the degree of closeness of these measurements gives precision It is a measure of the degree of repeatability or reproducibility of the measuring system. What Is Meant By Loading? Answer : During the act of measurement the measuring instrument takes energy from the signal source or measured medium and thus the signal source is altered.

This effect is called loading. Answer : They are the logarithmic plots used to represent transfer functions They are used in the calculation of gain margin and phase margin. Answer : They are orthogonal everywhere in the flow field. Answer : e. Answer : Axial pump has maximum specific speed and reciprocating pump has minimum. Answer : In a kinematic pair, if the elements have surface contact when in motion, the pair is called lower pair and if elements have line or point contact the pair is called higher pair.

Answer : Inversions are different mechanisms obtained by fixing different links in a kinematic chain but keeping relative motions of links unchanged with respect to one another. A kinematic chain with 'n' links can have 'n' inversions. Answer : A basic kinematic chain consists of four kinematic links and a compound kinematic chain is a constrained chain of more than four links.

A chain is constrained if no. Answer : A mechanism consists of links forming a constrained kinematic chain. Its function is basically to transmit or modify motion. A machine is a mechanism but here we are concerned with forces to be transmitted and it is used to modify mechanical work.

Answer : The function of a transducer element is to sense and convert the desired input into a more convenient and practicable form to be handled by measurement system. Answer : The direction of tangential acceleration may be same or opposite to that of angular velocity. Answer : Revolute pair—single degree of freedom. Screw pair—one degree of freedom. Answer : It controls the piston position for cut off of steam, for release of steam and compression position for steam in cylinder.

Answer : Corliss valve reduces condensation, provides independent control on admission, cut off, release and compression, and reduces driving power requirements. Define Primary And Secondary Transducers? Answer : A primary transducer senses a physical phenomena and converts it to an analogue output. Answer : The axes of spin, precession, and applied gyroscopic torque are contained in two planes perpendicular to each other, and planes of spin, precession, and applied gyroscopic torque in the three planes perpendicular to one another.

Answer : Shear forces between fluid particles and boundary walls and between the fluid particles themselves, result from the viscosity of the real fluid. What Is Best Hydraulic Section? Answer : Best hydraulic section is one in which for a given cross-section area, the channel section has least wetted perimeter.

Answer : It is defined as the energy head measured with respect to the channel bottom at the section. At any section, it is equal to sum of the velocity head and the water depth at the section.

Answer : Critical depth is the depth, at which the discharge may be delivered through the section at minimum energy. What Causes Boundary Layer Separation? Answer : Nose radius is favourable to long tool life and good surface finish.

A sharp point on the end of a tool is highly stressed, short lived and leaves a groove in the path of cut. What Is Open Channel Flow? Answer : Open channel flow has a free water surface which is normally subject to the atmospheric pressure. Steady open channel flow : In this case the discharge and water depth at any section in the reach do not change with time during the period of interest.

Unsteady open channel flow : In this case the discharge and the water depth at any section in the reach change with time. Uniform open channel flow : In this case the discharge and the water depth remain the same in energy section in the channel reach. It is mostly steady. It may be steady such as flow over a spillway crest or unsteady as in the case of flood waves or tidal surge. When Does Wake Occur? What Is Hydraulic Radius? Define Flow Work? Answer : Flow work is the amount of mechanical energy required to push or force a flowing fluid across a section boundary.

Answer : Dimensional analysis is the mathematics of dimensions and quantities and provides procedural techniques whereby the variables that are assumed to be significant in a problem can be formed into dimensionless parameters, the number of parameters being less than the number of variables. Answer : It is the ratio of area and the top width of the channel section. What Is Hydraulic Jump? Answer : It is a natural phenomenon in open channel.

It is an abrupt reduction in flow velocity by means of a sudden increase of water depth in the down stream direction. Through a hydraulic jump, and high-velocity supercritical flow is changed to a low-velocity subcritical flow. What Is Gradually Varied Flow? Answer : The changes in water depth in the open channel take place very gradually with distance. Depending on the channel slope, the surface conditions, the sectional geometry, and the discharge, these may be classified into five categories : steep channel, critical channel, mild channel, horizontal channel, and adverse channel.

Explain 5 Types Of Channels? Answer : Chills are used to achieve directional solidification. What Is Tumbler Gear Mechanism? Answer : Tumbler gear mechanism is a mechanism consisting of number of different sized gears keyed to the driving shaft in the form of cone and is used to give the desired direction of motion of the lathe spindle. Answer : It is the ratio of the size of the surface imperfections to the inside diameter of the pipe.

What Is Conicity? Answer : The ratio of the difference in diameter of the taper to its length is termed conicity. Answer : When water is brought by pipes to a junction where more than two pipes meet, them the total amount of water brought by pipes to a junction must always be equal to that carried away from the junction by other pipes, and all pipes that meet at the junction must share the same pressure at the junction. Answer : Pipe network comprises a number of pipes connected together to form loops and branches.

For a network,. What Is Hardy-cross Method? Answer : It is a commonly used computer program for a pipe network. Explain Water Hammer? Answer : The force resulting from changing the speed of the water mass say in a pipe due to sudden change of flow rate may cause a pressure rise in the pipe with a magnitude several times greater than the normal static pressure in the pipe. Answer : They get collected at the center of the casting. Answer : Hydraulic similitude is the principle on which the model studies are based.

Dimensional analysis is the analysis of the basic relationship of the various physical quantities involved in the static and dynamic behaviors of water flow in a hydraulic structure. Answer : Geometric similarity : It implies similarity of form.

The model is a geometric reduction of the prototype and is accomplished by maintaining a fixed ratio for all homologous lengths between the model and the prototype. Kinematic similarity : It implies similarity in motion.

Kinematic similarity between a model and the prototype is obtained if the homologous moving particles have the same velocity ratio along geometrically similar paths. It involves the scale of time as well as length. Define Reynolds Law? Answer : When the inertial force and the viscous force are considered to be the only forces governing the motion of the water, the Reynolds number of the model and the prototype must be kept at the same value.

Answer : While machining ductile materials at high speed. How Cavitation Causes Damage? Answer : In a a closed system pipelines, or pumps , water evaporates rapidly in regions where the pressure drops below the vapour pressure. This phenomenon is called cavitation. The vapour bubbles formed in cavitation usually collapse in a violent manner, which may cause considerable damage to the system. Answer : Arbor torque can be smooth end by increasing number of teeth, using higher spiral angle of teeth, using higher cutting depth.

Answer : Webs are the metal column in the drill which separates the flutes. What Is Bluff Body? Answer : It is a body with such shape that the flow is separated much ahead of its rear end resulting in a large wake, the pressure drag being much greater than the friction drag. What Is Bulk Modulus? Answer : It is the ratio of hydrostatic stress to volumetric strain within the elastic limits.

Define Boundary Layer? Answer : It is the fluid layer in the neighborhood of a solid boundary where the effects of fluid friction are predominant. What Is Creep Flow? Answer : It is flow at very low Reynolds number where viscous forces are larger than the inertia forces. What Is Torricellis Theorem? Answer : According to it velocity of jet flowing out of a small opening is proportional to the square root of head of liquid above it.

Answer : Usual symptoms of cavitation of pump are noise, vibration, a drop in head and capacity with a decrease in efficiency, accompanied by pitting and corrosion of the impeller vanes. Repeated erosive action results in complete honey combing and total destruction of blade, with resultant loss in pump performance. Answer : It depends upon the impeller diameter and its rotation speed. Answer : Electrolyte should be chemically stable and have high electrical conductivity.

Answer : For a. Answer : Efficiency of a pump centrifugal depends on the size, speed, and proportions of the impeller and casing. Answer : Cavitation in centrifugal pumps depends on the velocity of water entering the impeller and on the relative velocity of the impeller blades where the water is picked up. Answer : The losses in a centrifugal pump are : Friction losses due to eddies in flow, leakage, friction loss due to rotation of impeller in chamber of water, gland and bearing power losses.

Answer : In order to avoid cavitation, the suction lift and the operating speed must be carefully chosen. Answer : If speed of a reciprocating pump is increased beyond a limit, then atmospheric pressure would be insufficient to force water into the pump at the same speed as the piston.

This would a break in the continuity of the water in suction pipe cavitation and give rise to vibration, noise, and chemical attack by any dissolved gases which may be released from the water owing to the high vacuum and the breaking of the water column. Answer : The different operations done in slotter are :. Answer : Positive displacement in rotary pumps is achieved in two ways :. Answer : The flow and power vary as size2 when the geometric size changes as inverse of change of speed.

Answer : The incidence of cavitation is detected by the following in order of appearance. How Cavitation Erosion Is Assessed? Answer : Cavitation erosion is assessed by depth of attack or weight of metal removed. What Is An Arbor? Answer : An arbor is an accurately machined shaft for holding and driving the arbor type cutter.

It is tapered at one end to fit the spindle nose and has two slots to fit the nose keys for locating and driving it. Answer : Ratio of maximum velocity to average velocity should be 2. Answer : It is equal to weight of the liquid above the curved surface.

Answer : It depends on pipe diameter and the condition of the pipe. Answer : Potential flow assumes viscous forces to be zero but same is considered larger than inertia forces in creep flow. Answer : Mach no.

Froude number is significant in the study of ship hulls. Geometric similarity is mainly for same shape for model and prototype, kinematic similarity is concerned with streamline pattern, whereas dynamic similarity concerns the ratio of forces. Answer : Uniform ramming results in greater dimensional stability of a casting. Answer : Friction drag is experienced on separation of boundary layer. Answer : These have fine grain structure with high density. Answer : It is shaped to suppress the flow separation about the body and to shift the boundary layer separation to near most part of body to reduce the wake size.

Answer : Entrance length of flow is the initial length in which the flow develops fully such that the velocity profile remains unchanged downstream.

For turbulent flow in smooth pipe, entrance length is taken as 50 x diameter of pipe. Answer : Friction drag is the drag force exerted by a fluid on the surface due to friction action when the flow occurs past a flat surface at zero incidence. Pressure drag is the additional drag force on account of the differences of pressure over the body surface when flow occurs past a surface which is not everywhere parallel to the fluid stream. Pressure drag depends upon separation of boundary layer and the size of wake.

Friction drag is due to shear stresses generated due to viscous action. Answer : When specific mass flow is not able to take place in a pipe line. Answer : In streamline body the shape is such that separation in flow occurs past the nearmost part of the body so that wake formed is small and thus friction drag is much greater than pressure drag. In bluff body the flow gets separated much ahead of its rear resulting in large wake and thus pressure drag is much greater than the friction drag.

Answer : Dressing is the process used to clear the cutting surface of the grinding wheel of any dull grits and embedded swarf in order to improve the cutting action. Truing is the process employed to bring the wheel to the required geometric shop and also to restore the cutting action of a worn wheel. Answer : Softer graders of wheel are required for internal grinding than for external grinding. Answer : Velocity profile is parabolic with zero velocity at boundary and maximum at the centre.

Shear stress distribution is linear, being maximum at boundary and zero at centre. Answer : The shape of such section is that which produces minimum wetted perimeter for a given area of flow and carries maximum flow. What Is Follower Rest? Answer : For slender work a travelling or follower rest is used. This fits on the lathe - saddle and travels to and fro with it. By this means support is constantly provided at the position of cut. Thus the work piece being turn is rigidly held against the tool.

Answer : A sensitive drilling press is a light, simple, bench type machine for light duty working with infinite speed ratio. Answer : In carburised machine components, the process of carburisation introduces a compressive layer on the surface and thus endurance limit is increased.

What Is Anisotropy? Answer : The phenomenon of different properties in different directions is called anisotropy. Answer : Vapour pressure is the partial pressure created by the vapour molecules when evaporation takes place within an enclosed space. It becomes important when negative pressures are involved. Explain Absolute Viscosity? Answer : It is the ratio of shear stress and the gradient of velocity with distance between a fixed plate and moving plate Its unit is Pa.

Define Surface Tension? Answer : Surface tension of a liquid is the work that must be done to bring enough molecules from inside the liquid to the surface to form one new unit area of that surface.

Answer : Capillarity : The rise or fall of a liquid in a capillary tube caused by surface tension. The magnitude of rise or fall depends on the relative magnitudes of the cohesion of the liquid and adhesion of the liquid to the walls of the containing vessels. Capillarity is of importance in tubes smaller than 10 mm diameter.

Rise of liquid : Liquids rise in capillary tube when they wet and adhesion of the liquid to the walls is greater than the cohesion of the liquid. Fall of liquid : Liquids fall in capillary tube when they do not wet and the cohesion of the liquid is greater than the adhesion of the liquid to the walls. Answer : Perfect fluids are treated as if all tangential forces created by friction can be ignored. Which Factors Affect Tool Size? Answer : The motion of a fluid is fully known when the velocity of each of its particles can be specified.

Answer : A fluid is a substance that can't remain at rest under the action of any shear force. Answer : The specifications of vertical boring machine are :. Answer : The drill sleeve is suitable for holding only one size of shank. If the taper shank of the tool is smaller than the taper in the spindle hole, a taper sleeve is used. When the taper tool shank is larger than the spindle taper, drill sockets are used to hold the tools.

Drill sockets are much longer in size than the drill sleeves. What Is Non Barotropic Fluid? Answer : Fluid such as air for which the density is not a single-valued function of the pressure aerostatics. Answer : By international agreement, the standard atmospheric pressure is defined as Answer : Acoustic velocity is the speed of a small pressure sound wave in a fluid. Answer : Centipoise is the unit of dynamic viscosity.

Stoke is defined as 1 square centimeter per second. What Is Saybolt Seconds Universal? Answer : Saybolt Seconds Universal SSU is the unit of viscosity and is equal to the time required for a gravity flow of 60 cc through saybolt universal viscometer.

Answer : Cohesion is the attraction of like molecules. Answer : Gear hobbing is a continuous indexing process in which both cutting tool a hob and work piece rotate in a constant relationship while the hob is being fed into work.

Hob is also imparted a radial feed. Gear shaping uses a pinion type of cutter which is reciprocated with required cutting speed along the face of workpiece and is gradually fed radially to plunge. Continuous generation motion is obtained by feeding cutter to full depth and rotating the cutter and workpiece slowly. Answer : It represents the compressibility of a fluid. It is the ratio of the change in unit pressure to the corresponding volume change per unit of volume. What Is Isentropic Exponent?

Answer : It is the ratio of the specific heat of a gas at constant pressure to the specific heat at constant volume. Answer : Ideal fluid is one for which resistance to shearing deformation is zero. Non-newtonian fluids deform in such a way that shear stress is not proportional to the rate of shearing deformation.

Define Centroid Of The Area? It is also the centre of gravity. Answer : The pressure exerted when a solid or liquid is in equilibrium with its own vapour is called vapour pressure.

It is a function of the substance and its temperature. Answer : If at every point in the continuum, the local velocity and other fluid property, remains unchanged with time, it is referred to as steady flow. Answer : Groundwater occurs in permeable, water-bearing geologic formations known as aquifers. Unconfined aquifer : It is a water-bearing formation with a free water table, below which the soil is saturated.

Answer : The channels may be classified as rigid boundary or mobile boundary channels. Mobile boundary channels include rivers and unlined alluvial canals, the boundaries of which are made of loose soil which can be easily eroded and transported by flowing water.

The study of flow of water in mobile boundary channels is dealt in fluvial hydraulics. Answer : Specific weight of liquid and the depth below the free liquid surface. Answer : Hoop tension is created in the walls of a cylinder subjected to internal pressure. Longitudinal tension in thin-walled cylinders closed at the ends is equal to half the hoop tension. Answer : Force exerted by a liquid on a plane area A is equal to the product of the unit weight pg of the liquid, the depth hcg of the centre of gravity of the area, and the area.

Answer : The horizontal component of the hydrostatic force on any surface is equal to the normal force on the vertical projection of the surface and acts through the center of pressure for the vertical projection.

Vertical component of the hydrostatic force on any surface is equal to the weight of the volume of liquid above the area and passes through the e.

Answer : The horizontal component of the total hydrostatic pressure force on any surface is always equal to the total pressure on the vertical projection of the surface, and can be located through the center of pressure of this projection.

The vertical components of the total hydrostatic pressure force on any surface is always equal to the weight of the entire water column above the surface extending vertically to the free surface, and can be located through the centroid of this column. Answer : Force on a vertical projection of the curved surface.

State Archimedes Principle? Answer : Any weight, floating or immersed in a liquid, is acted upon by a buoyant force equal to the weight of the liquid displaced. This force acts through the center of buoyancy, i. Answer : Center of buoyancy is the center of gravity of the displaced liquid and buoyant force acts through it. Answer : A submerged body floats in stable equilibrium when the center of gravity of the body lies directly below the center of buoyancy.

What Is Neutral Equilibrium? Answer : A submerged body is in neutral equilibrium for all positions when the center of gravity of body coincides with the center of buoyancy.

Answer : Stability of floating objects depends upon whether righting or overturning moment is developed when the center of gravity and center of buoyancy move out of vertical alignment due to the shifting of position of center of buoyancy.

Answer : Two examples of products made by direct extrusion are : gear profile, solder wire. Two examples of reverse impact extrusion are : Short tubes of soft alloys, tooth paste containers. Answer : Cup shape is best suited by drawing operation. Conical shape is easiest to produce by spinning operation. Answer : A floating body is stable if the center of gravity is below the metacentre. Define Pipe Flow? Answer : The weight of liquid vertically above the curved surface. Answer : Disposable tips are usually indexable type and have a number of cutting edges.

Very convenient gripping devices for holding such inserts on tool holders are available. A wide variety of ready made inserts are available which require no grinding or adjustment. Answer : Canned cycles are fixed cycles for general sequences of operations. For drilling operation, sequence of operations will be movement of drill or workpiece to position of actual drilling, movement of drill downwards till it is in the proximity of workpiece, the movement of drill at desired feed rate to sufficient depth of hole, retracting the drill above the workpiece.

Answer : True one-dimensional flow occurs when the direction and magnitude of the velocity at all points are identical. Velocities and accelerations normal to the streamline are negligible.

Two dimensional flow occurs when the fluid particles, move in planes or parallel planes and the stream-line patterns are identical in each plane. Answer : Irrotational flow : An ideal fluid flow in which no shear stresses occur and hence no torques exist.

Rotational motion of fluid particles about their own mass centers can not exist. It can be represented by a flow net. Rotational flow occurs when the velocity of each particle varies directly as the distance from the center of rotation.

Answer : In steady flow, at any point, the velocity of successive fluid particles is the same at successive periods of time. Answer : Uniform flow occurs when the magnitude and direction of the velocity do not change from point to point in the fluid. Non uniform flow occurs when velocity, depth, pressure, etc. Answer : Stream lines are imaginary curves drawn through a fluid to indicate the direction of motion in various sections of the flow of the fluid system. There can be no flow across a streamline at any point.

Stream tube represents elementary portions of a flowing fluid bounded by a group of streamlines which confine the flow. Define Vorticity? What Is Irrational How? Answer : If a flow is uniform in one region without rotation , this property is conserved as the fluid moves into a region of space where the motion is not uniform, and the flow is termed irrotational flow.

What Is One-seventh Power Law? Answer : According to one-seventh power law of turbulent, velocity variation corresponds to a much favoured velocity profile and the mean velocity increases as the one-seventh power of the distance from the boundary wall. Answer : It is equal to the volume of the liquid displaced. The line of action of buoyant force acts through the centroid of the displaced volume of the fluid.

What Is Metacentre? Answer : Metacentre is the point at the intersection of the buoyancy with the vertical axis of the body.

Define Prandtl's Pitot-static Tube? Answer : It is a combination of pressure probe and pitot tube. It is widely used for pressure measurements in wind-tunnel installations.

Define The Term Fluid Friction? Answer : The deformation of real fluids is resisted by forces caused by internal friction or viscosity. Viscosity is that property of a real fluid which creates shear forces fluid friction between two liquid elements. Answer : Hydrodynamic bearings are more suitable at high speed, better tolerances, quiet operation, higher capacity to withstand shock, lesser space requirement, better life under fatigue conditions etc.

Answer : Jig clamps and locates parts in positive manner and guides cutting tools drills, reamers, taps etc. Fixture is bolted or fixed securely to the machine table so that work is in correct location ship to the cutter. Fixtures are used for mass milling, turning and grinding, etc. Answer : Both jig and fixture positively locate, hold and clamp the workpiece. Jigs guide the tool for drilling etc but fixture has no facility to guide the cutting tools.

Jigs are used for drilling etc and fixture for mass milling, turning, grinding, etc. Answer : Relative density is that pure number which denotes the ratio of the mass of a body to the mass of an equal volume of a substance taken as a standard. Viscosity of a fluid is that property which determines the amount of its resistance to a shearing force. It is due primarily to interaction between fluid molecules.

Answer : For cutting right hand helical gear right side of milling table is tilted up from normal position by the helix angle. For cutting left hand helical gear, right side of table needs to be tilted down at helix angle, all other settings remaining unchanged.

Answer : Hydrostatic paradox is the phenomenon that the floor load of water in vessels of different shapes carrying water at same level depends only on the area of the bottom surface and not on the shape of the vessel.

Define Buoyancy In Brief? Answer : Buoyancy is the vertical force exerted on the body by the fluid at rest. The buoyancy of a submerged body in a fluid at rest is equal to the weight of the fluid displaced by the body and it acts upward through the center of gravity of the displaced volume the center of buoyancy. Answer : Meta center should be above the center of gravity. What Does Continuity Equation Represent?

Answer : It relates mass rate of flow along a stream tube. Answer : When conditions do not change with time at any point. Answer : If flute submerged in a drilled hole, the chips disposal passage is blocked and the drill will get jammed in the hole. Answer : Drills used for brass and other soft materials and thin sheets need not be provided with any helix angle, to prevent the lips digging into the workpiece.

Answer : In case of laminar flow, the velocity distribution follows a parabolic law of variation. The maximum velocity at center of pipe is twice the average velocity. For turbulent flow, more uniform velocity distribution results.

Answer : When the cutting lips are not provided with clearance angles. Answer : Small drills less than 12 mm diameter are provided with straight shanks which can be held in Dhiren chucks.

Bigger drills have tapered shank using self holding Morse tapers which prevent gravitational fall of drill. Answer : The main factors that are responsible for the formation of built up edge are :. Answer : The energy line is a graphical representation of the energy at each section. Hydraulic grade line lies below the energy line by an amount equal to the velocity head at the section.

There is a continuing threat to these forests from exploitation for timber, fuelwood and charcoal. The mature trees shed varying numbers of acorns annually. Scientists suggest that shedding excess numbers allows the oaks to satiate nut gathering species which improves the chances of germination. Every four to ten years, certain oak populations will synchronize to produce almost no acorns at all, only to rain them down excessively the following year, known as a "mast" year.

The year preceding the mast year is thought to starve off the mammal populations feeding on the supply, thereby increasing the effectiveness of the overproduction in the mast year that follows. Sudden oak death Phytophthora ramorum is a water mould that can kill oaks within just a few weeks. Oak wilt , caused by the fungus Ceratocystis fagacearum a fungus closely related to Dutch elm disease , is also a lethal disease of some oaks, particularly the red oaks the white oaks can be infected but generally live longer.

Other dangers include wood-boring beetles , as well as root rot in older trees which may not be apparent on the outside, often being discovered only when the trees come down in a strong gale.

Oak apples are galls on oaks made by the gall wasp. The female kermes scale causes galls to grow on kermes oak. Oaks are used as food plants by the larvae of Lepidoptera butterfly and moth species such as the gypsy moth , Lymantria dispar , which can defoliate oak and other broadleaved tree species in North America. A considerable number of galls are found on oak leaves, buds, flowers, roots, etc.

Examples are oak artichoke gall , oak marble gall , oak apple gall, knopper gall , and spangle gall. A number of species of fungus cause powdery mildew on oak species. In Europe the species Erysiphe alphitoides is the most common cause. A new and yet little understood disease of mature oaks, acute oak decline , has been reported in parts of the UK since The oak processionary moth Thaumetopoea processionea has become a serious threat in the UK since The caterpillars of this species defoliate the trees, and are hazardous to human health; their bodies are covered with poisonous hairs which can cause rashes and respiratory problems.

In California, oaks are affected by the fungal disease foamy bark canker. The eastern grey squirrel Sciurus carolinensis is an invasive species across North America and Europe where they are known to strip bark off of a variety of large trees, including oaks. Bark stripping can result in the death of the leading shoot and decreased crown size. The countries with the highest numbers of threatened oak species according to the report are China with 36 species, Mexico with 32 species, Vietnam with 20 species and the USA with 16 species.

While the cause of decline is still partly unknown for some species, the main causes the scientists determined were climate change and invasive pests in the US, and deforestation and urbanization in Asia. In the Himalayan region of India, oak forests are being invaded by pine forests due to the increase in temperature.

The associated species of pine forest may cross frontiers and become new elements of the oak forests. In eastern North America, rare species of oak trees include scarlet oak Quercus coccinea , chinkapin oak Quercus muehlenbergii , and post oak Quercus stellata. The leaves and acorns of the oak tree are poisonous in large amounts to livestock including cattle , horses , sheep , and goats due to the toxin tannic acid , causing kidney damage and gastroenteritis.

Symptoms of poisoning include lack of appetite , depression, constipation, diarrhea which may contain blood , blood in urine , and colic.

The exception is the domestic pig , which may be fed entirely on acorns in the right conditions, and has traditionally been pastured in oak woodlands such as the Spanish dehesa and the English system of pannage. Acorns are also edible by humans, after leaching of the tannins. The oak is a common symbol of strength and endurance and has been chosen as the national tree of many countries. In England, oaks have been a national symbol since at least the sixteenth century, often used by Shakespeare to convey heritage and power.

In England today they remain a symbol of the nation's history, traditions, and the beauty of its countryside. Already an ancient Germanic symbol in the form of the Donar Oak , for instance , certainly since the early nineteenth century, it stands for the nation of Germany and oak branches are thus displayed on some German coins, both of the former Deutsche Mark and the current euro currency.

The oak is the emblem of County Londonderry in Northern Ireland , as a vast amount of the county was covered in forests of the tree until relatively recently. The name of the county comes from the city of Derry , which originally in Irish was known as Doire meaning "oak".

Iowa designated the oak as its official state tree in ; and the white oak is the state tree of Connecticut , Illinois and Maryland. The northern red oak is the provincial tree of Prince Edward Island , as well as the state tree of New Jersey. The live oak is the state tree of the US state of Georgia. The oak is a national symbol from the Basque Country , specially in the province of Biscay. The coat-of-arms of the municipality Eigersund , Norway features an oak leaf.

Oak leaves are traditionally an important part of German Army regalia. It is also known as the Iron Eagle. They also symbolize rank in the United States Armed Forces. A gold oak leaf indicates an O-4 major or lieutenant commander , whereas a silver oak leaf indicates an O-5 lieutenant colonel or commander.

Arrangements of oak leaves, acorns and sprigs indicate different branches of the United States Navy staff corps officers. If a member of the United States Army or Air Force earns multiple awards of the same medal, then instead of wearing a ribbon or medal for each award, he or she wears one metal representation of an " oak leaf cluster " attached to the appropriate ribbon for each subsequent award.

The oak tree is used as a symbol by a number of political parties. The prehistoric Indo-European tribes worshiped the oak and connected it with a thunder or lightning god, and this tradition descended to many classical cultures.

In Greek mythology , the oak is the tree sacred to Zeus , king of the gods. In Zeus's oracle in Dodona , Epirus , the sacred oak was the centerpiece of the precinct, and the priests would divine the pronouncements of the god by interpreting the rustling of the oak's leaves.

As in other Indo -European faiths, Taranis , being a thunder god, was associated with the oak tree. There has even been a study that shows that oaks are more likely to be struck by lightning than any other tree of the same height. In Norse mythology , the oak was sacred to the thunder god, Thor. Thor's Oak was a sacred tree of the Germanic Chatti tribe. The oak also appears in the Hebrew tradition.

In the Bible , the oak tree at Shechem is the site where Jacob buries the foreign gods of his people Gen. Also, Joshua erects a stone under an oak tree as the first covenant of the Lord Josh. In Isaiah 61, the prophet refers to the Israelites as "Oaks of Righteousness". Absalom's long hair 2 Samuel gets caught in an oak tree, and allows Joab to kill him.

Vereration of the oak survives in Serbian Orthodox Church tradition. Christmas celebrations include the badnjak , a branch taken from a young and straight oak ceremonially felled early on Christmas Eve morning, similar to a yule log. In recent times, only the branches are collected, brought home, and ceremoniously thrown into a stove or church bonfire. In another tradition, a z apis lit. Reverence for zapisi probably originated in pre-Christian times, and they long remained places of public gathering and even of Christian worship where churches were not available.

Even in modern times, cutting down zapis oaks can result in public outcry, even for projects like road building. He is born on Yule and rules from Ostara to Mabon. Several oak trees, such as the Royal Oak in Britain and the Charter Oak in the United States, are of great historical or cultural importance. Millais painted the picture in Hayes, Kent , from a local oak tree that became known as the Millais Oak. Approximately 50 km west of Toronto, Canada is the town of Oakville, Ontario , famous for its history as a shipbuilding port on Lake Ontario.

The city of Raleigh, N. The Jurupa Oak tree — a clonal colony of Quercus palmeri or Palmer's oak found in Riverside County, California — is an estimated 13, years old. Large groups of very old oak trees are rare [ why? One venerable group found in Poland, is about years old, as assessed by dendrochronology. In the Roman Republic, a crown of oak leaves was given to those who had saved the life of a citizen in battle; it was called the " civic oak crown ".

Category: Individual oak trees. From Wikipedia, the free encyclopedia. For other uses, see Oak disambiguation , Oak Tree disambiguation , and Quercus disambiguation. Genus Quercus of flowering plants in the beech family Fagaceae. See why. January See also: List of Quercus species. Play media. See also: List of Lepidoptera that feed on oaks. Main article: List of notable trees.

3d Cnc Wood Carving Software Error Free Woodworking Plans For Bench Seat Rights Jim Thorp Lumber Products Inc Amazon Wood Furniture Projects Pdf 04