Explore BrainMass

Explore BrainMass

    Mechanical Engineering

    Shearing stress in glued splice

    Determine the shearing stress in the glued splice, when the splice angle is 30 degrees instead of 60degrees. P = 1400lbs. See attachment for diagram.

    Determine Mass Flow Rate

    Water enters a 2 meter diameter pipe at a temperature of 23 deg C. The water leaves the pipe at a temperature of 97 deg C The laminar flow rate is such that the Reynolds number is 800. What is the mass flow rate? a) Less than or equal to 0.5 kg/sec. b) Equal to or greater than 0.2 m/sec. c) Greater than 0.5 kg/sec

    Determining Shape Factor: Thermal Conductivity and Heat Loss

    A thin disk is maintained at 75 degrees celsius and placed on the surface of a large medium maintained at 10 deg C. The thermal conductivity of the medium is 1.4 W/m-deg C, and there is a heat loss of 36 W. The shape factor, S is closest to: a) 20 cm b) 40 cm c) 60 cm d) 80 cm.

    Determine heat flow and thermal resistances

    Heat flow through a uniform wall will: a) increase as the thermal resistance increases b) increase as the thickness of the wall increases c) decrease as the thermal differences on each side of the wall increases d) decrease as the thermal resistance increases

    Determine Fourier Number

    Compare two identical steel spheres, except the first has a two inch diameter while the second sphere has a four inch diameter. The larger sphere will have a Fourier number approximately: a) half that of the smaller sphere b) four times larger than that of the smaller sphere c) twenty-five percent of the value of

    Thermal Conductivity

    A 4 m diameter sphere is embedded in insulation. The sphere contains a liquid-ice mixture maintained at 0 deg C. The ambient temperature surrounding the insulation is 25 deg C. The heat loss is 400 W. What is the temperature conductivity of the insulation? a) Less than 0.5 W/m-deg C b) 0.5 to 1.0 W/m-deg C c) Gre

    Find the closest ambient temperature

    A fireclay brick cube, 10 cm in length is removed from a furnace where it was maintained at a temperature of 500 degrees C. The brick cube is then placed in ambient temperature conditions. The heat flow from the brick is 400 Watts. The closest ambient temperature is: a) 300 deg C. b) 200 deg C. c) 100 deg C. d) 0 d

    Tire Explosion Prediction Math Model

    You witnessed the failure of a nylon rim which exploded injuring the person filling the tire with air. Develop a documented mathematical model that predicts the time required to reach a specific pressure. Your results are to be tabulated and plotted. Specifically predict the time to change from 100 kPa to 800 kPa. Assume the pro

    Matlab Functions: Two Row Vectors as Inputs

    Write a Matlab function that will accept two row vectors (A and B) as inputs. The function computes the row vector C that is the term-by- term product of A and B (that is, C1= A1*B1, C2=A2*B2, and so on), and that then computes the values of the function sin(x) for each value of C and stores these values in the row vector D. The

    Determine the Radius of Curvature

    For the composite bar indicated (see attachment), determine the radius of curvature caused by the couple of moment 70 Nm. a) 9.16 mm b) 12.73 mm c) 11.87 mm d) 10.41 mm

    Determine Stress on a Given Beam

    For the beam in the attachment, determine the stress at point D located 32mm below point A. a) 18.6 MPa b) -15.8 MPa c) 19.2 MPa d) 18.1 MPa

    Spherical Hankel Functions

    Please see attached file. Show that spherical Hankel functions of the first and second kind represent, respectively, radial traveling waves in the -r and +r directions. Assume time variations of and large argument asymptotic expansions for the spherical Hankel functions.

    Maximum Normal Stress Due to Bending

    For the beam illustrated (see attachment), determine the dimension b for which the maximum normal stress due to bending is 40 MPa. a) 7.45 mm b) 8.95 mm c) 8.33 mm d) 9.36 mm

    Largest Allowable Square Cross Section

    Determine the largest allowable square cross section of a steel shaft of length 6 m if the maximum shearing stress is not to exceed 135 MPa when the shaft is twisted through one complete revolution. Use G = 77.2 GPa.

    Determine the maximum allowable stress

    Knowing that, for the plate shown (see attachment), the allowable stress is 24 ksi, determine the maximum allowable value of P when r = 3/4 in. a) 35.42 kips b) 12.89 kips c) 43.27 kips d) 25.71 kips

    tensile force and corresponding normal stress of a wire

    A 28-ft length of 0.25-in.-diameter steel wire is to be used in a hanger. It is noted that the wire stretches 0.55 in. when a tensile force P is applied Knowing that E = 29 X 10 (to the 6th power) psi, determine (a) the magnitude of the force P, (b) the corresponding normal stress in the wire. a) 1.19 kips; 51.68 ksi b) 2.

    Kinetics of Particles and Newton's Second Law

    Determine the maximum theoretical speed that may be achieved over a distance of 50 m by a car starting from rest, knowing that the coefficient of static friction is 0.80 between the tires and the pavement. Assume four-wheel drive. In answering this problem, how can you use the coefficient of friction without mass?

    Simple Vapor Power Plant

    Steam enters the turbine of a simple vapor power plant with a pressure of 160 bar and a temp of 560 C and expands adiabatically to 0.08 bar. The isentropic turbine efficiency is 85%. Saturated liquid exits the condenser at 0.08 bar and the isentropic pump efficiency is 85%. Determine a) enthalpy of steam leaving the turbine

    Mechanical Vibration and Springs

    The machine shown in the figure is rigidly anchored on a rigid concrete block and the mass of both is 3000 kg. The block has height h = 1 m and square horizontal section with a = 1.2 m and is supported at the corners by 12 springs of stiffness k = 2000 N/m. i) Derive the equations of motion of the system using both Newton's

    Mechanical Vibration

    The machine shown in the figure is rigidly anchored on a rigid concrete block and the mass of both is 3000 kg. The block has height h = 1 m and square horizontal section with a = 1.2 m and is supported at the corners by 12 springs of stiffness k = 2000 N/m. Solve only the second part: (see attachment for diagram) ii) Find t

    Range of Velocity for the pitching wedge

    A pitching wedge a golfer is using gives the ball an initial angle of 50 degrees, what range of velocities (Vo) will cause the ball to land within 3 ft. of the hole? (the hole is 30 ft. from golfer). Assume that the hole lies on the plane of the ball's trajectory. I need help setting this problem up to start.

    Determine Stress

    Knowing that the couple shown acts in a vertical plane, determine the stress at (a)point A. (b) point B.

    Rate of Heat Generation

    A fillet weld is used to join two medium carbon steel plates each having a thickness of 5.0mm. The plates are joined at a 90 degree angle using an inside fillet corner joint. The velocity of the welding head is 6mm/sec. Assume that the cross section of the weld bead approximates a right isosceles triangle with a leg length of 4.

    Finding Metal Removal Rate

    In an electrochemical machining operation, the frontal working area of the electrode is 2.5in squared. The applied current=1500amps, and the voltage=12volts. The material being cut is pure aluminum, whose specific removal rate is 1.26 x 10^-4 in^3/amp-min. If the electrochemical machining process is 90 percent efficent, det

    DB - Find the capacity of a cylindrical tank

    1. Find the capacity of a cylindrical tank that is 250 feet in diameter and 30 feet high? 2. In the above problem, what is the capacity if the tank is 75% full, and what is the capacity in gallons? 3. If 50 pounds of chlorine are mix with 100 pounds of water, what is per cent chlorine solution that is made? 4. Find

    Calculating Modulus of Rupture

    Please help with the following problem. See the attached wood block diagrams. If a break load of 250 lbs. is applied to the first wood specimen, how do I determine the Moment of Inertia and calculate the Modulus of Rupture? The only difference between the specimens per the attached diagram is that a 1/4" x 1/4" key-way is

    Future Value of sums of money over eight years

    Your rich godfather has offered you a choice of one of the three following alternatives: $10,000 now; $2,000 a year for eight yeaers; or $24,000 at the end of eight years. assuming you could earn 11 percent annually, which alterantive should you coose? If you could earn 12 percent annually, would you still choose the same altera