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Mechanical Engineering

Thermodynamic Equilibrium

For a system to be in thermodynamic equilibrium, do the temperature and the pressure have to be the same everywhere? Explain.

Assignment Question 3 in Applied Mechanics

Fig. Q3 shows a rigid light beam which is hinged at O to a wall. The beam carries a point mass of m at the free end. The beam is connected at its mid-point to a spring (stiffness k) which is also connected to a support that moves with a vertical motion y = Y sinwt. A damper (coefficient c) connects the mid-point of the beam to a

Tank flow rate

With the valve closed, water flows from tank A to tank B as shown in the attachment. What is the flow rate into tank B, when the valve is opened to allow water to flow into tank C also? Neglect all minor losses and assume that the friction factor is 0.02 for all pipes.

Cam Curve Design

Design a three-dwell cam to move a follower from 0 to 2.5" in 40deg, dwell for 100deg, fall 1.5" in 90deg, dwell for 20deg, fall 1" in 30deg, and dwell for the remainder. The total cycle must take 10sec. Plot the s,v,a,j diagrams. The polynomial method is to be used to solve the equation. For the graphs, Mathcad or similar progr

Finding Vertical Distance in Pipe Line System

For the system in attachment, calculate the vertical distance between the surfaces of the two reservoirs when water at 10 degrees celcius flows from A to B at the rate of 0.03 m^3/s. Both pipes are cast iron and the elbows are standard. The total length of the 3" pipe is 100 meters. For the 6" pipe, it is 300 meters.

Automobile Pump Power

Gasoline is pumped from the gas tank of an automobile to the carburetor through a 10 ft long, 1/4" diameter fuel line of steel tubing. The line has five 90 degree smooth bends with r/d of 6. The gasoline discharges through a 1/32" diameter jet in the carburetor to a pressure of 14 psia. The pressure in the tank is 14.7 psia.

Proeutectoid Phase

Consider 1.0 kg of austenite containing 1.15 wt% C, cooled to below 727 degrees Celcius (1341 degrees Farenheit). a) What is the proeutectoid phase? b) How many kilograms each of total ferrite and cementite form? c) How many kilograms each of pearlite and the proeutectoid phase form? d) Schematically sketch and label t

Dynamics Problem

In the pulley system shown, object "A" moves downwards with a velocity of 3m/s. Determine the magnitude and direction of the velocity of object "B".

Mass Fractions

For the following problem, can I get the full solution (show your work) with explanation as to how you arrived at the answer. For a lead-tin alloy of composition 80 wt% Sn-20 wt% Pb and at 180 degrees Celsius (355 degrees Farenheit) do the following: a) Determine the mass fractions of alpha and beta phases b) Determine the ma

Stress Analysis of a Hollow Circular Tube Supported in a V-block

I am trying to find out stresses in a circular hollow tube that is sitting in a V-block and subjected to a vertical point force all along its length. I have done quite a bit of work but have some doubts about my analysis. The question may not be as straightforward as it seems. Please see the attached WORD file for all the det

NC Programming Created

Create an nc part program for making the slot shown in the attachment.The cutter diameter is 3/16 inch. The starting point is (0,0) at 2 inches to the left and 2 inches below the lower left corner of the part. There is also an example with a fully worked out solution included in the attachments. Write also the apt geometry and


2) See attachment for diagrams for both questions. 1) Two water manometers are connected to a tank of air. One leg of the manometer is open to 100kPa absolute pressure while the other leg is subjected to 90kPa. Find the difference in deflection between both manometers, delta ha - delta hb. 2) The inclined differential

Beam deflection and Stress at centroid?

Sometimes the term centroid throws me for a loop. So, how would I set this problem up? I'm asked to determine the deflection of the tip of a beam and max direct stress and location for a 2000N load. Given load=2000N, on the tip of a 1m beam. Beam dimensions are H=80mm B=W=40mm and t=thickness of 1.5mm.

Determine modal ratios

For the two degrees of freedom structure shown, what are the values of the modal ratios if m1 = m2 = m, k1 = k, and k2 = 3k See Attached for question and details.

Determine Viscous Damping Coefficient C

A Mass-Spring-Damper is tested to determine the value of the viscous damping coefficient c. Assume k = 10 lb/ft and m = 2 slug. The vibrational amplitude is observed to decrease by 33% of its initial value after two consecutive cycles. What is the value of the viscous damping coefficient c? a. 0.9376 b. 0.8442 c. 0.779

Simple Beam Concentrated Load at a Point

Draw the shear and bending moment diagram for the beam shown and find the value of the maximum bending stress. This case is a Simple Beam Concentrated Load at a Point. Solving for Moment of inertia, c-value, Reactions, Shear, Moment, and Max Bending Stress are discussed. Two different solution methods are discussed.

Find the fuel consumption

In the an ideal turbo jet, the engine is designed such that the turbine work is divided equally between the compressor and the propeller. The gas from the turbine discharges to a nozzle for additional thrust. Consider such an engine where the air enters the diffuser at 200 m/s, 40 kPa, 240 K, and a flow rate of 40 kg/s. The comp

Ideal vapor-compression refrigeration cycle

An ideal vapor-compression refrigeration cycle, with ammonia as the working fluid, has an evaporator temperature of -20c and a condenser pressure of 12 bar. Saturated vapor enters the compressor, and saturated liquid exits the condenser. The mass flow rate of the refrigerant is 3 kg/min. Determine: - The coefficient of perf

Ideal Vapor-Compression Refrigeration System

An ideal vapor-compression refrigeration system operates at steady state with Refrigerant 134a as the working fluid. Superheated vapor enters the compressor at 30 lbf/in2, 20F, and saturated liquid leaves the condenser at 140 lbf/in2. The refrigeration capacity is 5 tons. Determine: -the compressor power in hp -the rate of h

Question about Multipal choice question on mechanics

A car with a mass of 2,000. kilograms is moving around a circular curve at a uniform velocity of 25 meters per second. The curve has a radius of 80 meters. What is the centripetal force on the car? a. 625 N b. 703N c. 15,625 N d. 20,250 N

Rankine Open Cycle

Rankine Open Cycle has an Ideal steam reheat cycle where steam enters the high pressure turbine at 3 MPa and 400C and then expands to 0.8 MPa. It's then reheated at constant pressure of 0.8 MPa to 400C and expands to 10kPa in the low-pressure turbine. Each turbine stage is entropic efficiency of 85% FWH is open T-S diagram for c

Brayton Cycle Gas Turbines

Large stationary brayton cycly gas turbine power plant delivers a powr output of 100MW to an electric generator . Minimum temperature is 300K so T1= 300k max temp is 1600k so T3= 1600k Minimum pressure in the cycle is 100kpa compressor pressure ratio is 14 to 1 so p2/p1 = 14 but turbine efficiency is 85% and compressor efficienc

Mobility and transit time

Consider the 2.0micrometer long GaAs device where the E-field is 5kV/cm and Mn*=.067M0. (a) Calculate the transit time of an electron through the device if the mobility is 8000 cm^2V-s. (b) The mean free path of an electron (average velocity x scattering time) is the average distance an electron travels between two consecu

Excess carrier concentrations and diffusion current density.

Consider a bar of p-Si that is homogeneously doped to a value of 3x10^15 at T=300K. The applied electric field is zero. A light source is incident on the end of the semiconductor. The excess-carrier concentration generated at x=0 is deltap(0)=deltan(0)=10^13/cm^3. Neglect surface effects. Mun=1200/cm^2/Vs. Mup=400/cm^2/Vs.

Quasi Fermi Level

Q. An n-type silicon sample with Nd=10^16cm-3 is steadily illuminated such that g'=10^21cm-s^-1. If tn0=tp0=10^-6s, calculate the position of the quasi-Fermi levels for electrons and holes with respect to the intrinsic level (assume that ni=1.5x10^10cm^-3).

Non-uniform Flow Compared to Average Velocity

Compare a nonuniform flow with the average velocity. See attachment for full problem including diagram. A laminar pipe flow that is fully developed has a velocity profile Has a parabolic velocity profile that is: Compare the average velocity ( ) with the axial direction momentum flow rate using the non uniform velocity d

Barrage Energy Example

The area of morecambe bar at high water is approx. 200km^2. At low water most of the bay is exposed sand. for this exercise, we could assume that on average the sand slopes evenly so that half way between high and low tide the area of water is 100km^2. The tidal range (between low and high tide) varies between 4m at neap tide

Difficulty over a problem relating to the motion of a projectile.

A player throws a ball with an initial velocity Vo of 15 m/s from a point A located 1.5 m above the floor. Knowing that the ceiling of the gymnasium is 6 m high, determine the highest point B at which the ball can strike the wall 18 m away. This problem was taken from the curvilinear motion of particles inside the kinematics