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Mechanical Engineering

Material properties question

1) Three samples of aluminum are subjected to a constant stress and the times required to produce a constant strain of 0.1% during steady state creep at different temperatures are shown in table 1 below. Temperature (00C) 151 205 258 Time (hours) 100 1.0 0.028 Use this information to determine grap

A 1000 m3/minute air stream at atmospheric pressure is at a temperature of 82.2oC

A 1000 m3/minute air stream at atmospheric pressure is at a temperature of 82.2oC and a humidity of 60%. We want to cool the air + water vapor to 8.9oC to condense the water vapor. Determine the sensible cooling and latent cooling required to drop the temperature of the air mass from 82.2oC to 8.9oC and condense the water vapor.

Calculating sensible heat, latent heat, and heat of vaporization of water

A 1000 m3/min air flow at 170 degrees F and containing 60% relative humidity needs to be cooled to 48 degrees F to promote condensation of the water vapor in the air. How would you calculate the sensible heat, the latent heat, and determine the latent heat of vaporization of the water vapor in this air stream as the air is co

Determining maximum value of the average normal stress

In the problem attached, why are the pins not included in the calculation of area when the links are in tension? But the pins are included in the calculation of area when the links are in compression. See attached file for full problem description.

Stress and Loads - largest permissible value load

The cross section of the beam AD in Question 1 (attached). 1. Knowing the allowable normal stress due to bending +110 MPa in tension and -150 MPa in compression, find the largest permissible value load W if beam AB is not overstressed. See attached file for full problem description.

Mass-flow rate

Consider a flow for which the velocity vector is: u=(U/L)(xi-2yj+zk) Compute the mass-flow rate across a plane of area A that is perpendicular to the x axis and lies at x=3L. The fluid density is d. I know that the mass-flow rate, M, is calculated by: M=Double integration [d(u*n)]dA I am having trouble setting up the i

What is the axial deformation in the link?

Each of the two vertical links BD has a uniform cross section 0.375 X 1.5 in. Determine the axial deformation and normal stress in each link for the loading shown. Determine the axial force in each link for the loading shown. Use E = 29 X 10^6 psi Axial deformation a. 0.00196 in b. 0.00392 in c. 0.00467 in d. 0.0

Determine the stress on a steel rod

The rod ABC is made of steel (E = 29 X 10^6 psi). Determine the normal stress in section BC. Determine the deflection at point B and C. See attached file for full problem description.

Introductory Thermodynamics - rigid tank

A rigid tank with a volume of 2.5m^3 contains 5kg of saturated liquid-vapor mixture of water at 75 deg C. Now the water is slowly heated. Determine the temperature at which the liquid in the tank is completely vaporized. Also show the process on a T-v diagram with respect to saturation lines.

Hydrostatic Pressure and Forces

Determine the force due to hydrostatic pressure acting on the hinge of the gate shown. The fluid density is d and the width of the elliptical gate (out of the page) is 6H. (I have attached the picture provided) The answer is supposed to be: 21(pi)dg(H^3)/8

Hydrostatic relation

An empirical formula relating pressure and density for seawater w/ temperature held constant is: p/pa = (k+1)(q/qa)^7 - k where p= pressure pa = pressure at the surface k = dimensionless constant q = density qa = density at the surface Using the formula in the

Number sentences

Komodo dragons are the largest lizards known to man. A 250-pound dragon can eat enough food to increase it body weight by 1/2. Which number sentence could be used to find w, the weight of a komodo dragon after increasing it body weight by 1/2? If eight people share in eating 3/4 of a quart of ice cream, how much will each per

Finding Magnification factor M for Frequency Ratio

1) In the idealized model attached shown, m = 15 kg, k = 135 N/m, and the viscous damping ratio is 0.15. Assume that an external harmonic force F(t) = 15 cos 4 t acts on the system with F0=15 N and forcing frequency of 4 rad/s. i) Find the magnification factor M for the frequency ratio r of 1.382. ii) What is the amplitude o

Matrix equation of motion

1) For the two degree of freedom structure shown: i) what is the matrix equation of motion?. Assume that m1 and m2 oscillate harmonically with the same frequency but with different amplitudes X1 and X2 of x1(t) and x2(t). ii) what are the values of the amplitude ratios r1 and r2 if m1 = m2 = m, k1 = k, and k2 =3k? See a

Refrigeration problem.

A large refrigeration plant is to be maintained at -15C, and it requires refrigeration at a rate of 100kW. The condenser of the plant is to be cooled by liquid water, which experiences a temperature rise of 8C as it flows over the coils of the condenser. Assuming the plant operates on the ideal vapor-compression cycle using re

The compression ratio of an air-standard Otto cycle is 9.5

The compression ratio of an air-standard Otto cycle is 9.5. Prior to the isentropic compression process, the air is at 100 kPa, 17 C, and 600 cm2. The temperature at the end of the isentropic expansion process is 800K. Using specific heat value at room temperature, determine: 1. The highest temperature and pressure in the

An ideal vapor-compression refrigeration cycle uses R-134a

An ideal vapor-compression refrigeration cycle uses R-134a as the working fluid in an air-conditioning system. The refrigerant enters the compressor as a saturated vapor at 40 °F and leaves the condenser as a saturated liquid at 130 °F. The mass flow rate of the refrigerant is 1.5 lbm/s. Calculate the following: a. The hea

Moment of Force Problem

1. Three forces F1, F2, and F3 or magnitude 40 N, 100N and 20 N are acting on a point. The direction of the forces are 0,-30 and +120 degrees from the positive X axis. Determine the magnitude and direction of the resultant force.

Advanced Dynamics

Collar C slides relative to the curved rod at a constant speed u, while the rod rotates about the horizontal axis at the constant rate. Determine the acceleration of the collar in terms of theta.

Employing the ideal gas model, determine the change

Employing the ideal gas model, determine the change in specific entropy between the indicated states, in Btu/lbmol?ºR. Solve 2 ways: Use the appropriate ideal gas table AND also by using a constant specific heat value. a) Air, P1 = 1 atm, T1 = 40 ºF, P2 = 1 atm, T2 = 400 ºF b) Air, P1 = 20 psia, T1= 100 ºF, P2 = 60 psia,

A heat pump is used to maintain a house at a constant temperature of 23 °C

A heat pump is used to maintain a house at a constant temperature of 23 °C. The house is losing heat to the outside air through the walls and the windows at a rate of 60,000 kJ/hr while the energy generated within the house from people, lights, and appliances amounts to 4000 kJ/h. For a Coefficient of Performance (COP) of 2.5,