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Mechanical Engineering

Modulus of Elasticity

A linear isotropic material has the shear modulus of elasticity G of 11.5*10^6 psi and the Poisson's constant v of 0.3. How do I determine the Young's modulus of elasticity E?

Tensile stress

A 3.14insq. cross sectional area steel tension rod carries a load of 3140lbf. How do I calculate the tensile stress in the rod?

Analyze Planner Equilibrium

The structure shown in Figure Q. 1 (see attached) is a pin-jointed section of a canopy and carries a single load of 4 kN acting at the lower right-hand joint. Show that the section is stable and, determine the following: (a) The directions of the support reactions by locating the point of concurrency for the external force

Engineering statistics

(a) From the following table of durabilities of marine coatings on electrical boxes, find the following quantities: Durability (ASTM Salt Spray Test) Class Frequency Hours Midpoint Class Interval xi fi 100-103.9 102 6 104-107.9 106 12 108-111.9 110 18 112-115.9 114 28 116-119.9 118 14 120-123.9

Maximum stress

Find the maximum value of S>0 if a stress of... is applied to a 60 deg boron/epoxy lamina. Apply Maximum Stress failure, Tsai-Hill failure and Tsai-Wu failure theories.

Internal pressure

2. The control of pulling force is of critical importance to pultrusion process. What are the major force components in different process stages? And how would they respond to the change of resin viscosity, pulling speed, temperature, coefficient of thermal expansion of composite mixture, degree of shrinking, and coefficient of

Hoop stress

1. A pressure vessel is made of a cylindrical composite part produced by filament winding. Hoop winding is used in which the number of winding layer is 5 and the wall thickness for each layer is 1mm. The diameter of the vessel is 0.5m. The fiber material is known to be S-glass with a tensile strength of 4.5GPa, and the matrix m

Reaction forces

A horizontal beam under load can roll along a vertical guide as shown. What are the reaction loads at A? Shear? Axial?

Method of Joints

A truss is loaded as shown. How do I find the magnitude of the force in members DB and BF? Can it be done without the equations of equilibrium?

Shear diagrams

A beam is under applied loads shown. How can I describe the shear diagram for sections I through III?

Trusses

Are the weights of members usually included in the analysis of truss structures?

Body in Equilibrium

When a body is in equilibrium, are the magnitudes of the unknown forces or moments independent of where they are located on the structure?

Longitudinal versus Transverse Vibrations in a bar

A 48 inch long by 2 inch diameter round steel rod (E=30e6 psi, density=0.28 lb/in3) is fixed at one end and free at the other. If the rod is struck transversely so that there is both a longitudinal and transverse wave generated, how long does it take for each wave to complete a cycle? If you wanted to record 5 cycles for each

Single degree of freedom vibration problems with forcing functions

Need help with this Undergraduate problem where two dampers are in series. For a vertical spring/damper system with mass (M) and a harmonic forcing function, Fmax Cos [omega x t] , two dampers are in series with coefficients, C1 and C2, and a single spring with constant, k. Determine the amplitude of the steady-state disp

Angular Velocity: Slender Bar, Stepped Disk and Slender Rods

Please see the attachment for proper formatting and diagrams. 1. The slender bar with a mass of 4 kg is released from rest at an angle of 35 degrees. What is the angular velocity of the bar when it is vertical? a. 0.667 rad/s b. 1.06 rad/s c. 0.888 rad/s d. 1.74 rad/s e. 2.31 rad/s 2. The stepped disk

Manufacturing processes factors

1. Explain the factors involved in selecting the appropriate type of abrasive for a particular grinding operation. 2. What are the consequences of allowing the temperatures to rise during grinding? (Q. 25.38). 3. What are the implications of using a smaller abrasive grain size (higher grit number) in a bonded grinding wheel?

Moment of Inertia Problems

The three problems attached having to do with moment of inertia of things like a yo-yo. I need help setting them up. Please send explanations with the answer so I can see how your answer was achieved.

Mass of Inertia and Angular Acceleration

1. Two slender rods are welded together at right angles and released from rest as shown. The two welded bars rotate freely around point C. Each bar is 10 lbs and is 1.5 ft long. At release, what is the acceleration magnitude of point B? 2. A vertical 0.2-meter-long slender bar with a uniform cross section is released from res

Manufacturing Processes

Please answer the following questions: Certain manufacturing processes have the following characteristics described below. Please characterize the process in terms of : Type of process, state of workpiece material and the type of process energy used. 1. A metal is cast into a mold and solidifies 2. A metal bar is reduce

Mechanical Vibration Analysis

For this two degree fo freedom model, how do I find the matrix equation of motion? How do I find the value of the modal ratios if m1=m2=m, k1=k and k2=3k? If a force of 25sin3t is applied to m2, how do I find the value of the response if m1=m2=1 slug, k1=10lb/ft and k2=30lb/ft?

Mechanical Vibration Analysis

In this idealized model, m=1 slug, k=9lb/ft, and the viscous damping factor is 0.15. How do I find the range of frequency ratios for which the magnification will be greater than 1? How do I find the forced response for A=1, and forcing frequency of 4rad/sec?

Mechanical Vibration Analysis

How do you find the equation of motion for an idealized model? For this model how do you find the periodic time (time in sec) and the natural frequency (rad/sec)? Please see attached for diagram.

Turbomachinery and Reaction Turbines

1) Steam at 15 bar and 350 degrees C is expanded through a 50% reaction turbine to a pressure of 0.14 bar. The stage efficiency is 80% for each stage and the reheat factor is 1.05. The expansion is to be carried out in 10 stages and the required power is 6000 kW. Calculate the steam flow required, assuming that the stages all de

Turbomachinery: Reaction Turbines

Please help with the following problem. Sketch the fully annotated velocity triangles for a Parsons turbine stage. Use your sketch to show that the specific work produced per stage is given as w_stage = (C_b)^2 [1 + 2(f/C_b)(cot(B_1))]. At a particular stage of a Parsons reaction turbine, the mean blade speed is 60 m/s an

Turbomachinery: Impulse Turbine

1) The steam from the nozzles of a single wheel impulse turbine discharges with a velocity of 600 m/s at an angle of 20 degrees. The blade wheel rotates at 3000 rev/min and the mean blade radius is 590 mm. The axial velocity of the stream at the exit from the blades is 164 m/s and the blades are symmetrical. Sketch the annota

Mass Moment of Inertia and Translational Motion

1. Calculate the mass moment of inertia about the x axis. The total mass of the object is 13 kg. 2. The plate with two holes is made of steel with a density of 7800 kg-m3. The radius of each hole is 5 cm. Determine its mass moment of inertia about the z-axis. 3. Determine the mass moment of inertia about the y axis. The t

Moment of Inertia and Translational Motion

1. A four-wheel truck that has a mass of 5,000 kg accelerates forward. The coefficient of friction for the front and back wheels is 0.2 and 0.4, respectively. What is the acceleration of the truck? Assume that the friction force on both the front and rear wheels are at a maximum and both are about to slip. 2. Each of the 2 b

Turbomachinery: Impulse and Reaction Turbines

1. An impulse air turbine rotor with a blade speed (U) of 300 m/s is measured to have a relative rotor inlet velocity (W_1) of 750 m/s at an angle of 69 degrees and an outlet relative velocity (W_2) of 660 m/s. Th temperature and pressure in the rotor are 375 K, 0.83 bar. Calculate the rotor efficiency, rotational speed and powe

Calculating the Second Moment of Area

It is necessary to design a square-section composite bar that will withstand an applied load without deflecting more than a specified amount.The design specification for the bar, including its dimensions and loading criteria, is given below. Using the formula below, calculate the second moment of area of the bar and use this