PE: Final Review
Two 1/4 in steel strips are held by an aluminum rivet with a 1/8 in diameter. Because the rivet is in single shear, the applied load is eccentric, causing the joint to bend under stress. Which stress is greatest on this rivet?
-"System of forces" to find bending moment -Find max normal stress from bending in beam stress eqn -Find MoI -Calculate bearing stress with area of bearing -Calculate shear stress with cross section -Compare all 3 stresses
What are the main characteristics of a fluid?
-Compressibility -Inability to support shear -Viscous properties to resist instantaneous velocity changes -Pressure at any point in a fluid is the same in all directions
A sensitive piece of equipment, which has a given mass, is mounted to its base by four springs in parallel, each with the equivalent stiffness. Other equipment in the area of the equipment causes a vibration in the base at a given frequency. Only 20% of the force the base exerts on the equipment is allowed in order to prevent equipment damage. Assuming the system has no damping, the stiffness of the springs should be most nearly?
-Convert frequency to circular freq (f*2pi) -Find the vibe transmissibility eqn and set it equal to 0.2 -Given lack of damping, set damping coefficients as zero -Solve vibe tran eqn for r to set equal to frequency ratio eqn -Solve for k, find individual k
At a shipping facility, two conveyors move boxes. Upper is horizontal, moves at X m/s. At the end, boxes fall into a second conveyor at a A degree slant. The first conveyor is B m from the floor. How do you find the distance along the length of the second conveyor?
-Create new coordinate axis with the base at point of impact of the box -Use kinetic energy equations to solve for height -Solve for the conveyor triangle
For frame shown, weight of each member is negligible. Most nearly, what is the axial force in the center member, and is it in tension or compression?
-Do method of joints -Sum of forces and sum of moments -System of eqns
A cylindrical pulley has a 12 in diameter and a 1 in thickness and exerts a weight of 5 lbf. Attached to the pulley is a 20 lbf load on a cable. How long does it take for the load to fall 15 ft?
-Do sum of forces between Tension and Weight (make sure g_c used) -Solve for tension -Find MoI of pulley -Combine force and moment eqns and solve for angular acceleration -Use "constant acceleration" eqn to solve for time
A x lbm weight rotates in a vertical plane at the end of a A ft rope. When theta = B degrees, magnitude of the tangential velocity is C ft/s. What is the tension in the cord?
-Draw a FBD for weight. -Tension you are solving for is made up of the tangential
A phase diagram for an alloy of tin and another metal is shown. Most nearly, what amount of tin is in the solid phase at 210?
-Draw line down from solid at given temperature to the composition axes -Similarly, since alloy given, find the percent solid times the amount of the metal
A cylindrical pulley has a X in diameter and a A in thickness, and exerts a weight of B lbf. Attached to the pulley is a C lbf on a cable. How long does it take for the load to fall D ft?
-Find MoI of the pulley -Sum of forces -Sum of moments -Solve for angular acceleration -Convert angular to linear acceleration, and solve for time in Lin motion
A given lbm mass is connected to the top of a vertical steel rod with a given length and diameter. Rod is clamped securely at the base, creating an inverted pendulum oscillator. An integral damping system is modeled as a certain damping coefficient. Neglecting the rod mass, what is the damping ratio?
-Find MoI of the rod -Find stiffness for that beam with equivalent masses section -Calculate natural frequency with free vibe eqn -Combine crit/damp ratio eqns and solve
A simply supported shaft is loaded as shown. Diameter is 2 in, and shaft is 90 in long. MoE is 30,000,000 psi. What is the max deflection?
-Find beam eqn for deflection -Find MoI -Solve for deflection
A motor with a certain hp turns a shaft at a given speed. Shaft steps down in diameter from one to another, and the shoulder has a given radius. What is the max torsional shear stress?
-Find eqn for shoulder w/ torsion concentration factor -Solve for polar MoI -Solve for torque from motor -Solve initial eqn for shear
A steel stepped shaft is dimensioned as shown. The steel has a given shear modulus. The equivalent torsional spring constant of the shaft is most nearly?
-Find equivalent k for each step of the shaft using spring eqns -Sum the springs up with spring eqns
A X in diameter steel support wire with a modulus of elasticity of A psi is normally strung between two utility poles B ft apart under C lbf of tension. A winch maintains tension by stretching the wire. A new procedure requires the wire to be under D lbf of tension. The length of additional wire the winch must pull to reach the new tension is?
-Find length change that happens with first tension -Find length change with new tension -Calculate difference
To test electrical conductance of a metal, ends of a 1 ft long piece of 0.05 in x 0.05 in square rod made of metal are attached to a 2V battery. A current of 15 A measured. What is the resulting electrical conductivity?
-Find resistance using Ohm's law -Look up "electrical properties" and find resistivity eqn -Solve for resistivity and divide 1 by it
When a X lbm mass is attached to the end of a spring, the spring stretches a certain length. A dashpot with a damping coefficient opposes movement of the mass, initially at rest. What is the damping ratio?
-Find spring constant with nat frequency vibe eqn -Find nat freq of system using k -Combine damping ratio and crit damp eqns and solve
A simply supported rectangular section steel beam is a given width, thickness, and length. Bending stress is limited to a given value, and so is deflection. Neglect buckling. What is the max point load the midpoint can support?
-Find the MoI of the beam -Use eqn for max moment of beam and deflection given beam tables -Use eqn for max bending load in beam stresses -Combine eqns -Solve deflection eqn for load
A cube with X in edges is made from a brittle nickel alloy. The alloy has an ultimate tensile strength of A psi and an ultimate compressive strength of B psi. In use, the cube experiences combined forces of C lbf (tensile), D lbf (compressive), and E psi (shear). Factor of safety greater than F required. What is the failure mode of this material?
-Find the area of a face of the cube -Calculate tensile, compressive, max principal, and min principal and check their FS -If it fails among principal, it fails in shear -Else, in the respective stress
A X in long solid steel shaft with a given diameter is supported at each end by self-aligning bearings. Critical frequency needs to be raised at least 10 Hz higher. The density of the steel shaft is given, and the modulus of elasticity too. What is the min diameter of the shaft needed to get the increase in frequency?
-Find the beam deflection equation for a distributed load -Find MoI and solve deflection eqn (weight is density*l) -Find the frequency using free vibe eqn for displacement -Now solve the same free vibe eqn with new values -Set equal to beam eqn and solve for radius
A helical compression spring made of X in diameter steel wire has a A in outer diameter and a B in free length. Allowable shear stress is C lbf/in^2. The spring is dynamically compressed to D lbf. How do you find the factor of safety?
-Find the mean diameter -Calculate spring index using the equation given of D/d -Find the K factor using index -Calculate max stress -Ratio of allowable to max = factor of safety
A X ft long rod with a diameter of A in is used as a tie rod in a temperature controlled environment. The tie rod is designed to fail when the tension reaches B lbf and the rod is elongated by C in. What material is best suited for this?
-Find the modulus of elasticity and look up the material tables -Use the main MoE equation and solve for E -Compare MoE in the table to your value
A X in diameter pipe hanger rod is loaded in tension with a A lbf force. The rod is B in long and is made of material Z, which has the stress and strain properties shown in the graph. What will the total elongation be?
-Find the stress on the cross section of the rod -Use the data point on graph that obeys proportionality limit to calculate the deformation
A UNC bolt with a given diameter is nonplated with a black finish and is torqued to a given amount. What bold grade has a proof stress that satisfies the loading requirement for permanent connection?
-Find torque coefficient K in tables (nonplated, black) -Find preload with torque equation that uses coefficient -Find proof load -Find proof stress -Go to tables and find grades with that proof strength
A bolt and nut are used to clamp two rigid steel plates that are each a given thickness. The bolt is 1/2 in 20 UNF with a given nominal size and modulus of elasticity. After fastening, the length of the bolt's threaded section that is still between the plates is given. The nut has a certain number of threads and is tighter until stress in bolt body is a certain value. No washers are used to clamp the plates. What is the bolt stretch?
-Find unthreaded length by (-) threaded parts -Solve for engineering strain and deflection -Use tensile stress area in UNF tables and find unthreaded area -Compare unthreaded sections and solve for stress -Solve for strain again then stretch
The control element of a fire alarm is a slender steel alloy rod. The rod is 2 in long and has a diameter of 1/16 in. The rod is positioned snugly between two solid plates (assume pinned connection). When the rod is heated from its normal temperature of 70 to 113, it must buckle, sending a signal to an alarm. The modulus of elasticity is 15 x 10^6 psi. What is the coefficient of thermal expansion needed using long column formulas?
-Look up "length factor" for long columns to check K -Use the critical long column load eqn to solve for load -Use load to find strain "engineering stress" -Use strain/temp change to find coefficient "thermal expansion"
The nut on a UNF grade 8 steel bolt is tightened a certain number of rotations from an initial unstretched grip length. The bolt has a given diameter and modulus of elasticity. Ignore threads/stress concentration. What is the stress in the nominal area of the bolt?
-Look up UNF table for threading for that size/grade -Calculate the pitch -Elongation is pitch*rotations -Combine stress and deflection equations and solve for stress
A course threaded Grade 8 bolt with a given nominal size is used in permanent application. What is the preload force on the bolt?
-Look up torque requirements for permanent app, find the eqn for preload -Look up SAE specs for bolts to find proof strength given dims and find area -Look up torque reqs again and find proof strength eqn, solve for preload force
In the reverted gear train, gears A and B have a diametral pitch of 10 teeth/in, and gears C and D have a diametral pitch of 12 teeth/in. The number of teeth on gear A is 30. The overall speed ratio is 11.5. How many teeth does gear D have?
-Meshing gears have same diametral pitch -Create equations using diametral pitch and teeth for each gear -Calculate first diameter then use center distance to calculate next -Use velocity ratio by using teeth (bottom up) -Use center distance eqn and solve for ND
A X lbf container is lifted by a winch on a A in diameter disk. The disk is mounted on the shaft of the winch, which is driven by the motor via a B:C gearbox. The gearbox experiences losses of 10%. The gear ratio of the gearbox is found with the given equation. How do you find the minimum required torque from the motor?
-Min required torque to lift container is found with the weight/torque equation -Now solve for the motor's torque (2 separate torques!)
Design specifications for a mass produced flange are shown. One flange is randomly selected for inspection. The diameter is measured as X in. Relative to datum A, what total amount of positional tolerance is most nearly available?
-Since datum specifies a circled M, indicating MMC know that bonus tolerance is available -MMC + the difference between the diameter given and the smallest diameter possible, or LMC
A cylindrical pressure vessel has an internal pressure of X psi. The pressure vessel has an internal diameter of A and a thickness of B. One end of the pressure vessel will be capped with a bolt-nut system. What force should the cap be capable of withstanding?
-Since only capped end needed, find internal pressure and the area of the end -Use the power force area eqn and solve for force
A timing belt runs around an X in diameter pulley and has A degrees of contact. The pulley runs at B rpm. The belt's mass is C lbm/ft. The tight side tension is D lbf, and the coefficient of friction is E. What is the slack side tension?
-Since the belt has mass, centrifugal belt eqn -Convert rpm to velocity by multiplying it by circumference
A v-belt connects drive pulley A, which operates a machine tool, to pulley B. The diameters of pulley A and B are given. Both diameters are to the depth of the v. The coefficients are given for each pulley. The tension on the belt it limited to a certain value. What is the largest torque that can be transmitted through the pulley system?
-Since the pulley cables have different tension, torque arises -Use the belt friction eqn to solve for the second tension (using drive tension as first) -Calculate max torque using moment (difference in forces*radius)
Truss 1 is modified by removing several members (mentioned) into a new truss. X amount of A lbf loads have been applied to the first truss at B ft intervals as shown, and consolidated on the new truss. The percent change in tension in one particular member that remained before and after is:
-Sum of forces and moments -Find a point between the member at the bottom of the truss -Use method of sections to cut member/whole truss in half -Solve for tension in member -Repeat for new truss and compare.
A flywheel and a gear are located on a stationary shaft supported by two bearings, as shown. The flywheel applies a X lbf vertical load, and the gear applies a A lbf vertical load. The diagram starts with one bearing, B in from the flywheel, C in from the second bearing, D in from the gear. At what locations on the shaft, as measured from the left, are shear forces undefined?
-Sum of forces to get equation for reaction forces -Sum of moments to solve reaction equation -Plot the shear diagram (start plotting then plot down upon interruption in force) -Points on vertical lines undefined.
Design engineers must select a structural polymer from the following list of materials. One critical dimension, fabricated to X in at A degrees Celsius, must not exceed B in at the operating temperature C degrees Celsius. Material weight must be under half of aluminum, which has a specific gravity of D. What is the best material?
-Test each material for the constraints mentioned -Eliminate the ones too heavy (SG), -Eliminate whose max temperature is below the operating -Use the thermal expansion equation to find lowest deformation
The slider crank assembly shown begins at rest in a straight configuration. The crank rotates clockwise and accelerates at X rad/sec^2. Slider is connected to A in long shaft which is connected to B in long crank. At C seconds, the velocity is most nearly?
-Use angular velocity equation, then solve for the position -Convert it to revolutions then multiply by 360 to use as the angle of crank -Ratio of velocity of arm and crank is equal to ratio of their lengths -Then solve for linear velocity
A pressure of X psi applied to A ft3 of liquid results in a volume change of B ft3. What is the bulk modulus of the liquid?
-Use bulk modulus equation that accounts for changes in volume and pressure
A pinion with a certain number of teeth will mesh with a gear rotating at a set speed. The pinion has a given circular pitch and is rotating at a set speed. What is the distance between the centers of the gears?
-Use circular pitch eqn to find pinion diameter -Use the diametral pitch eqn to find pitch -Solve velocity gear eqn -Use velocity to solve for other gear diameter -Solve for center distance
A bevel gear arrangement is shown. The speed of the pinion is raised to X% of its former rate. The diameter of the pinion is reduced by A%, and the transmitted tangential load, is raised to B%. To maintain the system, the horsepower must be changed. What is the percentage of power required?
-Use eqn for HP in gears that relates tangential load, horsepower, diameter, and speed -Replace the units with percentages and solve for change in HP
A hydraulic tubing is designed to withstand a given pressure. Tubings has a given outside diameter and a given yield stress. It has a known safety factor. What is the required wall thickness?
-Use eqn for pressure vessel cylindrical from Barlow that uses D -Solve for thickness and test need for thick-walled
A change of direction of motion can be achieved by a parallel bar mechanism, as shown. Motion of x starts with an angle of 0. How can the motion of y be described?
-Use eqn in trigonometry basics that relates x and y to angle -Solve eqn and take derivative wrt time -Solve for dy/dt and test an angle
In an engineering competition, students try to launch water balloons over a specified range using catapults and slingshots. The balloons must be launched horizontally from the roof of the engineering building, a specified height above the ground. All springs used in the competition must have a specific spring constant and be extended no more than a certain length. Each projectile water balloon weights a certain amount when ready to be launched. Under these conditions, what is the least number of springs in parallel that can send a balloon a certain distance ft?
-Use linear eqs to solve for time -Find the velocity needed to cross that range in that time -Find the KE and PE for balloons/springs -Create a ratio to solve
A solid steel shaft with a given diameter turns a cooling tower fan at a given speed. If the steel shaft has a given yield stress, what is the max horsepower transmitted?
-Use max shear stress failure eqn (Average Mech Properties) -Use the torsion max torque eqn, solve for torsion -Use the torsion power eqn and multiply torsion by ang velocity
A radial ball bearing has a basic static load rating of X lbf based on a life of A cycles. The bearing supports a B lbf radial load and a C lbf thrust load. The outer ring rotates, and there is no shock loading. How do you find the service life?
-Use relationships in the ball/roller section to find the ratio of radial load/thrust load. -Use the equation for e to find the components of the equivalent stress -Plug into the life cycle equation
A steel pressure vessel has a given outside diameter, given thickness for head and for shell, and a given corrosion allowance. Welds are spot radiographed, and operating temperature is given. The longitudinal joint governs the vessel design. Allowable stresses versus temp and weld joint efficiencies are given in tables. What is most nearly the max allowed pressure?
-Use table given to find allowable stress -Calculate thicknesses and inside radius after corrosion -Use the expanded cylindrical pressure vessel eqn to solve
A cylindrical spring with X coils (all active) is made of steel wire with a diameter of A in. The steel has a shear modulus of B psi. The design load of the spring is C lbf with a maximum deflection of D in. How do you find the mean spring diameter?
-Use the basic equation F = kx and solve for k -Solve for the mean diameter.
Two loads of a given weight are stacked a certain distance from the ends of a simply supported long beam with a given length. Choose the point of the max moment on the beam.
-Use the beam diagrams to find eqns -Verify calculations by solving for max moment and shear with reactions/moments
A ball bearing has a catalog load rating specified and a catalog speed rating specified for a certain amount of time. The bearing application has a design speed given for a certain amount of time. The relation constant for the bearing is given. The required radial design load is?
-Use the expanded ball/roller eqn because design and catalog loads/ratings used
A phase diagram for an alloy is made up of 30% tin and another metal, shown below. Most nearly, how much of the material is in the solid phase at 210?
-Use the lever rule equation using the two points on the tie line
A machine with a certain lbm is supported by a lighter structure. The displacement of the structure during a free vibration is shown. The mass is subject to oscillating force with variable frequency and a given magnitude. The formula for the amplification factor is shown. What is the largest displacement the force can cause?
-Use the natural log displacement equation for vibes -Solve the torsional vibe equation to solve for displacement -Find the natural frequency using period on graph -Use the free vibe eqns and solve for displacement
A machine weighing X lbm is supported by a lighter structure. The displacement of the structure during free vibration is shown. What is the damping coefficient for the system?
-Use torsional vibe eqn to find the displacement -Use the damping ratio displacement equation to solve for ratio -Solve the damped frequency, then convert to natural -Solve for the constant.
The bolted joint shown is designed to carry a specified shear force and to yield before the force exceeds a certain amount. Characteristics of candidate bolts are listed in a table. There are no threads in the shear plane. Which size bolt meets design specs?
-Use total shear area equation (bolts*surfaces*area) -Use the max shear stress theory eqn to solve for shear -Use shear bolt force eqn to solve for force
A pipe is carrying compressed air at a pressure X psi. The pipe has an internal diameter of A and the pipe has a thickness of B. The ends of the L length pipe is capped at both ends and sealed airtight. What is the hoop stress developed in the pipe?
-Verify if thin walled -Use tan stress eqn (hoop = tan)
The graph of engineering stress-strain for material W is shown. Poisson's ratio for the material is X. What is the modulus of elasticity of the material?
-Verify the axes of the graph - if strain is given as a percentage, it must be converted -Solve for MoE using the stress/strain equation
A spring pulley and mass system is shown. The spring constant is given. The pulley is massless, and its radius given. What is the frequency of vibration of a 20 kg mass once it is deflected and let go?
-Weight on the cable of the pulley is 2x weight of the mass -Use the "free vibe" eqn to solve for nat frequency
What institutions were responsible, in order, for: 1. Identifying steel 2. Standards for bolts in joints 3. Standards for pressure vessels 4. Defined fits
1. AIron and Steel 2. ASCI 3. ASME 4. ANSI
What is a low-carbon steel?
A steel with less than 0.3% carbon
How do fluids react to shear stresses?
All fluids will move when subjected to shear stresses
A X hp motor is spinning at A rpm. The output shaft of the motor is B in diameter and is welded to a large disk. Weld is made with an E80xx electrode. What is the minimum perimeter fillet weld size to withstand the shear stress of the motor output on the disk?
Calculate the torque on the shaft using the horsepower and torque equation. Find the yield strength of the electrode given. Use that to find the shear, then find the proper weld equation to solve
What metal is a good alloy for inhibiting corrosion in steel?
Chromium
Per manufacturer data, a DC shunt motor generates X kW of heat per A kW of rated power. The rated power is B hp and the rated torque is C ft-lbf at D rpm. Current through armature is E A. Heat loss is from armature. Resistance from armature is most nearly?
Convert hp to W and calculate how much HP is being lost to heat. Then use the equation for power and current to solve for resistance.
Strain gauges are placed on a machine support to measure the principal stresses, which measure X kip/in2, A kip/in2, and B kip/in2. The material is cast aluminum, and the tensile yield strength is C kip/in2. Using the max shear stress theory for ductile materials, what is most nearly the factor of safety for stress in the support?
Ductile materials in the max shear stress theory mean tensile and compressive stresses are equal. Find the max shear. Use the theory to calculate the allowable max shear. Then do allow/actual to find the FS
What is helium used for?
During TIG welding to protect aluminum and stainless steel from corrosion
From least to most adhesive, rank tape.
Electrical, masking, duct, and then rubber-modified epoxy tape
What plastic forming manufacturing process uses a parison?
Extrusion blow molding, where raw material is first melted and extruded into a hollow tube
The machined part shown is made from a homogenous material. Most nearly, where is the centroid based on a Cartesian coordinate system centered at the lower left bottom?
Find each shape's area, find each shape's centroid, then find the centroid of the centroids with the centroid equations
A milling operation is set up to slot a piece of low-carbon steel using a three flute, high speed end mill cutter with a diameter X in. Cutting speed for the tool against low carbon steel is A ft/min, and the chip per tooth is B in/tooth. What is the best feed rate for this operation?
First, calculate the rotational speed using the velocity/circumference. Flutes = teeth. Use the speed and other ratios to calculate the feed rate
When checking for wear, what value should be used to determine which to test first - greatest vibrational amplitude or rotational speed?
Greatest vibrational amplitude
What is brazing?
Group of welding process heated to 800 F that use nonferrous filler metals with low melting point, distributed by capillary action
What is forge welding?
Group of welding processes wherein coalescence is produced by heating in a forge or other furnace and by applying pressure or blows (hammer welding done in railroad/blacksmith)
What are the benefits of adding chromium to steel?
Hardness, strength, and corrosion resistance
What is a parison?
Hollow tube where raw material is first melted into from extrusion blow molding
What is argon used for?
In MIG welding to keep the arc confined
What is acetylene gas used for?
In high temp torches for brazing and flame cutting
The manufacturing document shown gives the dimensions, locations, and tolerances of a drilled circular disc. The diameter of pin gauge needed to check the location tolerance of the hole pattern from the primary reference datum is?
In order to check the location tolerance, you need the virtual size - subtract the MMC and the tolerance from the diameter
A cable runs through a set of pulleys and supports a weight, as shown. The pulleys are frictionless, and the weight at the end of the cable weights 100 lbf. The force on the cable at the left (3 pulleys) needed to support the weight is most nearly:
In the absence of friction in pulleys, tension is constant throughout. T = W
What are the benefits of adding molybdenum to steel?
Increases high-temperature strength and hardness
What is LMC?
Least material condition, configuration of unit that has the smallest amount of material
What is welding?
Localized coalescence of metals produced by heating to suitable temperatures with or without pressure, and with or without filler metal, with melting point at or below base metals (but above 800)
What metal is a good alloy for improving wear resistance for steel?
Manganese
Two lines in an oblique position are shown. The profile reference plane axes are shown. Which option represents a rear auxiliary normal view?
Match the reflections from the PRP lines as polar opposites
What is MMC?
Maximum material condition - the tolerances and limits that provide for unit with most material possible
Can carbon steels bear chromium alloy?
No
The manufacturing document for a block with a projecting cylindrical plug is shown. Most nearly, how many degrees of freedom are constrained by the datum B?
Observe the datum from different perspectives and count the ways it can be restricted in motion translationally and rotationally (primary -> tertiary datum)
A nickel plate is tested in a corrosive environment. The density of the nickel is X kg/m3. A A cm2 sample is exposed for B hours and loses C g. The predicted material loss from corrosion can be calculated given the equation. What is the predicted material loss?
Perform dimensional analysis and ensure units are fine
What technique do you use to compare two gears in mesh?
Pitches are the same, velocities are the same
How does injection blow molding work?
Raw material is first injected into a mold to create a preform, attached to a blow mold for the final part
How does compression molding work?
Raw material is placed between two mold halves that close around the charge
An input shaft and an output shaft are at an angle of 40 degrees to each other. Power transmission is done with a set of bevel gears. Which pitch cone angles are possible for the gear and pinion, respectively?
Since the shafts are at a specified angle, the pitch cone angles can only be within that angle, so their sum must add up
A piece of steel stock is milled down to a plate with a certain thickness. It is parallel and has a good surface finish. The tolerance of the thickness is approximately given. A hole is drilled in the plate with a diameter plus or minus a value. Within each tolerance, what is the least material condition dimension?
Since you want LMC, you need to find the configuration with least amount of material. That means you want the thinnest plate and the largest hole
What is the name of the joining process where metal parts are coalesced by using filler nonferrous metals distributed between properly fitted surfaces of joint by capillary attraction?
Soldering, where temps are heated to below 800 F
In order to control vibrations of an electronic system, the system is supported by an elastic pad. The system has a mass of X kg and a natural frequency of A rad/s. It is estimated that the system requires a damping ratio of B to manage vibrations. What is the required damping constant for the pad?
Solve for the spring constant using the natural frequency equation. Then use the two equations for critical damping and solve for the constant.
The force distribution on the frame shown is given by the equation. What are the reaction forces at A and B?
Solve the force distribution equation and integrate, then take derivative to find the position of the force. Use sum of moments and sum of forces to find reactions
What is a technique for turning a long taper on an engine lathe?
The tailstock offset, used for longe slender tapers. Workpiece is machined between the tailstock and headstock centers, and the tailstock is offset to make the taper angle.
How do fluid viscosities vary with temperature?
They don't all follow a rule - though temperature usually is inversely related, non-Newtonian fluids can increase or decrease with temperature
What is nitrogen used for?
To prevent oxidation when heat treating a part
A X in steel shaft is supported at each end by bearings. A A lbf gear is located B in from one end. The C in diameter shaft is specified to operate at no more than half the critical speed. The static deflection is D in. What is the maximum operating speed?
Use the equation for the undamped natural period of vibration, where your f is the critical speed. Divide it by 2 and convert to appropriate units.
What metal is a good alloy for improving toughness in steel?
Vanadium
What are some nondestructive methods of testing a welded joint?
X-rays, ultrasonic, radiography
