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# Mechanical Engineering

### Find the minimum-cost POS form

Find the minimum-cost POS form for the function: f(x1, x2, x3)= m(1,4,7)+D(2,5).

### 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

### Compute the Gains Function

Please see the attached file for the full problem description. A plant has a transfer function It is desired to use a negative unity feedback with a PID controller and a prefilter. The goal is to achieve a peak time of .75 second with ITAE-type performance. Compute the gains required to meet the design specification, ,

### Force, acceleration and mass

What force is required to accelerate a body with a mass of 15 kilograms at a rate 8/S2 ( the 2 is small obove the s)? a. 1.875 kg b. 23 kg c. 23N d. 120N

A car with a mass of 1,200 kilograms is moving around a circular curve at a uniform velocity of 20 meters per second, the centripetal force on the car is 6,000 newtons. What is radius of the curve? a. 160 meters b. 80 meters c. 32 meters or d. 16 meters?

### Mechanics: Efficiency of the Machine

A machine is supplied energy at a rate of 4,000 W and does useful work at a rate of 3,760 W. What is the efficiency of the machine? a. 92 percent b. 94 percent c. 96 percent d. 97 percent?

### Centripetal Force on a Car

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

### Apparent Density, Theoretical Density and Void Volume

A compacted body of iron powder is sintered into a 20mm-diameter, 45-mm-tall cylinder which, upon weighing, is found to have a mass of 98g. Calculate the apparent density, the percentage of theoretical density, and the void volume (porosity) in percent.

### Determine the change in entropy of the surrounding.

Liquid H2O at 8 MPa and 40 degrees C is heated reversibly at constant pressure until the temperature reaches 600 degrees C. Determine the change in entropy of the surrounding (universe).

### Tensile Stress in a Bar of Steel

A bar of steel 1 by 1½ in cross section and 6 in long is subjected to a pull of 6000 lb. What is the average tensile stress in the bar?

### Simulation block diagram and state equations

Simulation block diagram and state equations. See attached file for full problem description.

### 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

### Representative velocity profiles

Womersly’s Problem: Plot some representative velocity profiles for the purely oscillatory flow of a Newtonian fluid in a long, rigid, straight pipe at various phases of the flow (3-4). For these plots, use the values of constants given below: Constants: Velocity (u): 105 cm/s Diamter (d): 2.23 cm Kinematic viscosit

### Rankine Cycles

Consider an ideal steam reheat and regenerative cycle where steam leaves a steam gen and enters a high pressure turbine at 3 Mpa and T=400 C and is extracted to an open feedwater heater at 0.8 Mpa. The remainder is reheated to 400 C at this pressure which flows to the low pressure turbine stage. The condenser saturation pressure

### heat transfer rate and the rate that entropy is produced

A gearbox operating under steady state conditions recieves 24 hp along the input shaft and delivers 10hp along the output shaft. The outer surface of the gearbox is at 110F and has an area of 1.4 ft^2. The temperature of the surroundings away from the immediate vicinity of the gearbox is 70 F. For the gear box, determine a) the

### Diesel engine

A diesel engine has air before compression at 280 K and 85 Kpa. The highest temperature is 2219 K and the highest pressure is 6 MPa. Find the volumetric compression ratio and the mean effective pressure using cold air properties at 300K.

### Determine Dynamic Parameters of a Second Order System

Elaborate a Matlab model for this, using an non reinforced second order equation. M*d2y/dt2 + C * dy/dt + K* y =0

### Newtonian Physics: Balance Beam Problem Structuring

Need to obtain a working mathematical model of the balance beam problem, preferably with a cart, not a ball. i.e. Newtons laws leading through to equations of motion, aswell as transfer functions for use in matlab, any help will be much appreciated, thank you...

### Thin walled box beam with end load at an angle.

A box beam made from an extruded aluminium ally having 5 414 mm wall thickness is loaded by an inclined force P=100 N, as shown in the figure. Determine the maximum stress on section a-b. For the box beam, use the centreline dimension for finding I. (Note that the stress is far away from the support where large local stress co

### Wooden beam under constant load at an angle

A 150 &#61620; 200 mm wooden beam shown in Fig 9-4 (a) is used to support a uniformly distributed load of 4 kN (total) on a simple span of 6000 mm. The applied load acts in a plane making an angle, &#61537;, of 20&#61616; with the vertical, as shown in Fig 9-4 (b) and again in Fig. 9-4 (c). Calculate the maximum bending stress