At a point in a bracket, the stress on two mutually perpendicular planes are 100 N/mm² (tensile) and 50 N/mm² (tensile). The shear stress across the planes is 80 N/mm². Find using Mohr stress circle or otherwise calculate:

1. Magnitude and direction of the resultant stress on plane making an angle of 20⁰ with the plane of the first stress.
2. Maximum shear stress and location of its plane.

c. Principal stresses and the location of principal planes

Design any pneumatic system of any industrial application with at least 3 outputs.

Please describe the components used.

Example: Bottle Sorting and Labelling: The three outputs can be to sort the bottle by color or size then Seal the Bottle and later Put it in a box. This is just an example...you can use any.

A long, cylindrical, electrical heating element of diameter D= 10 mm, thermal conductivity k= 240 W/m·K, density ρ= 2700 kg/m³, and specific heat cp= 900 J/kg·K is installed in a duct for which air moves in cross flow over the heater at a temperature and velocity of 27°C and 15 m/s, respectively.
(a) Neglecting radiation, estimate the steady-state surface temperature when, per unit length of the heater, electrical energy is being dissipated at a rate of 1500 W/m.
(b) If the heater is activated from an initial temperature of 27°C, estimate the time required for the surface temperature to come within 10°C of its steady-state value.
Evaluate the properties of air at 450 K.

What is the value of the Reynolds number?

Re = 4613.05 (correct)

What is the value of the average Nusselt number?

not sure

What is the steady state temperature, in K?
got it correct

=666.96 K

What is the value of the Biot number?

Bi =0.0027

got correct

How long does it take for the element to come within 10°C of the steady state temperature, in s?

t= 168.21 correct

Knowing the steady state temperature, what is the actual value of the film temperature that should be used to find the air properties, in K? (Do not redo the problem.)

Tf=

(not sure )

1. A cylindrical shell is 3 m long; 1 m in diameter and the thickness of metal is 10 mm. It is subjected to an internal pressure of 150 N/cm². Calculate the change in dimensions of the shell and the maximum intensity of shear stress induced. Given E= 200 GPa and Poisson’s ratio =0.3.

b. Two shafts of the same material and same lengths are subjected to the same torque. If the first shaft is of a solid circular section, the second shaft is of hollow circular section, whose internal diameter is 2/3 of the outside diameter and the maximum shear stress developed in each shaft is the same, compare the weights of the shafts

heat transfer question, show equations, assumptions, calculations and steps clearly. will give thumbs up rating if solved correctly in 50 minutes

Write the Heat Diffusion Equation (HDE) in Cartesian coordinates and explain the meaning of every term.

A uniform supersonic airflow traveling at passes over a wedge (as Figure). An oblique shock, making an angle of 40° with the flow direction, is attached to the wedge under these flow conditions. If the static pressure and temperature in the uniform flow are 20k Pa, -10 °C, respectively. Determine the static pressure and temperature behind the wave, the Mach number of the flow passing over the wedge, and the wedge half-angle.

1. Three devices, X, Y and Z are connected in series to a hydraulic pump. Device X operates at 0.4 MPa, device Y operate at 0.8 MPa and device C operates at 1 MPa. Sketch the arrangement and placed a pressure indicator readings. (CO2,PO2,C3)

2. Three devices, X, Y and Z are connected in parallel to a hydraulic pump. Device X operates at 0.4 MPa, device Y operate at 0.8 MPa and device C operates at 1 MPa. Sketch the arrangement and placed a pressure indicator readings. (CO2,PO2,C3)

Air enters an air-conditioning system that uses refrigerant-134a at 30°C and 70 percent relative humidity at a rate of 4 m3/min. The refrigerant enters the cooling section at 700 kPa with a quality of 20 percent and leaves as saturated vapor. The air is cooled to 20°C at a pressure of 90kPa .

Determine the rate of dehumidification m˙w=   kg/min (Round to five decimal places)

Determine the rate of heat transfer Q˙out= kJ/min (Round to two decimal places)

Determine the mass flow rate of the refrigerant m˙R= kg/min (Round to three decimal places)

n-Octane (C8H18) is burned with 34 percent excess air, with 9 percent of the carbon forming carbon monoxide. Determine the maximum work that can be produced, in kJ/kg fuel, when the air, fuel products are all at 25°C and 1 atm.

I am trying to understand a few injection molding calculations. I will appreciate your assistance.

How do I calculate part weight for plastic injection molding?

Is it mass * density or volume * density?

My part is 29.126 grams and I am using  Polypropylene (PP) which has a density of 0.899 g/cm³ .

Therefore : 29.126 * 0.899= 26.184 grams

To convert to ounce: 26.184* 1/28.3495=0.9236 ounce

Is the above correct?

How do I calculate shot weight?  Please explain clearly and give and example.

How do I calculate core and cavity cost?

I will appreciate a clear and well written explanation because I want to understand how its done.

Thank you

Please refer to the article titled as “Sustainable Construction Excellence for a Better Future in Malaysia, published in The Ingenieur, Vol. 69 January – March 2017 by the Board of Engineers Malaysia.Elaborate on the “Paradigm Shift” which was outlined in the 11th Malaysian Plan and how would it affect our quality of life?

Establish a relationship between atomic structure, crystal structure, imperfections and mechanical properties of materials.