The ppf of the face for the BCC unit cell is greater than the face of the SC unit cell.

is it true or false, justify your reasoning.

A compressor is to run at 250 rpm and requires 75 kW. The drive is provided by V-belts from an electric motor running at 750 rpm. The pitch diameter of the pulley on the compressor is 750 mm and the centre distance between the motor shaft and compressor shaft is 1500 mm. Determine the number of V-belts required to transmit this power if each belt has a cross-sectional area of 375 mm2, density of 1000 kg/m3 and an allowable stress of 2.5 MPa. The groove angle of the pulley is 35° and the coefficient of friction between the belt and pulley is 0.25.

Consider a combined gas-steam power cycle. The topping cycle is a simple Brayton cycle that has a pressure ratio of 7. Air enters the compressor at 15 ºC at a rate of 10 kg/s and the gas turbine at 950 ºC. The bottoming cycle is a reheat Rankine cycle between the pressure limits of 6 MPa and 10 kPa. Steam is heated in a heat exchanger at a rate of 1.15 kg/s by the exhaust gases leaving the gas turbine, and the exhaust gases leave the same exchanger at 200 ºC. Steam leaves the high-pressure turbine at 1 MPa and is reheated to 400 ºC in the heat exchanger before it expands in the low-pressure turbine. Assuming 80 percent isentropic efficiency for all pumps and turbines,

1)  determine the steam temperature at the inlet of the high-pressure. (hint: trial and error)

2) determine the net power output of the combined plant.

3)  determine the thermal efficiency of the combined plant

A combined gas turbine–vapor power plant has a net power output of 200 MW. Air enters the compressor of the gas turbine at 300 kPa, 1200 K, and is compressed to 1000 kPa. The pressure ratio of the gas turbine cycle is 11. Steam leaving the turbine of the vapor power cycle are used to heat the steam at 6 MPa to 350C in a heat exchanger. The combustion gases leave the heat exchanger at 420 K. An open feedwater heater incorporated with the steam cycle operates at a pressure of 1 MPa. The condenser pressure is 10 kPa. Assuming isentropic efficiencies of 80 percent for the pump, 82 percent for the compressor, and 80 percent for the gas and steam turbines, determine (a) the mass flow rate ratio of air to steam, (b) the required rate of heat input in the combustion chamber, and (c) the thermal efficiency of the combined cycle.

Q5 (a) Compare the Direct and Indirect extrusion works with the aids of diagram.

(b) In metal forming, there were temperature ranges used including cold, warm and hot working.

(i) Compare between Hot and Cold working of metals.

(ii) Discuss the advantages and disadvantages for both processes.

(c) In designing and developing new products, engineers need to be aware the design consideration factors for plastic components. Give TWO (2) general design consideration factors, ONE (1) design consideration for extrusion process and FOUR (4) design consideration factors for moulding process.

Why is the effect of a rotating thin cylinder compared to the case of an internally pressurized thin cylinder?

Consider four identical circular Euler columns under a compressive axial load with a) one end fixed and the other pinned (or hinged or simply-supported), b) both ends fixed, c) both ends pinned (or hinged or simply-supported), d) one end fixed and the other free. What are the buckling loads Pcr for each one and which one is the strongest against buckling? Given are: the length L of the column and bending rigidity EI, ?

Under normal driving conditions, car tires can generate a fiction coefficient of approximately 0.7. Antilock braking systems can increase the effective coefficient of friction to as high as 1.0. For car traveling 65 miles an hour, determine the stopping distance for coefficients of friction of 0.7 and 1.0. How much more time do antilock brakes give the driver to respond. Also, why have antilock brakes not produced reductions in crash rates that were anticipated from this calculation?

1. Suppose a hollow cylinder made of SS 316 with the thermal conductivity of 16.26 W/m K, has inner diameter and thickness of 0.4 and 0.05 m, respectively and length of 1 m. Find the outer diameter of the cylinder (in meter)

2. Calculate the thermal energy generation, if the volumetric heat generation inside the cylinder equal to 2.1 x 10^5 W/m^3

3. If the outer diameter of cylinder is changed to 0.46 m and the cylinder is cooled by water at the temperature of 22°C, the heat transfer coefficient of fluid is 1100 W/m^2 K, and the volumetric heat generation inside the cylinder equal to 1 x 10^5 W/m^3 , calculate the steady state outer surface temperature (in °C)

4. By using the outer diameter of problem no 3, calculate the convective heat transfer (qconv) if the fluid and outer surface temperature at 25°C and 40°C, respectively, and the heat transfer coefficient of fluid change to 700 W/m^2

5. By using the outer diameter of problem no 3, the fluid and outer surface temperature at 25°C and 45°C, respectively, and heat transfer coefficient of fluid 1400 W/m^2 K. Calculate the inner surface temperature (in °C)

6. By using the outer diameter of problem no 3, and outer surface temperature of problem no 5, calculate the conductive heat transfer (qcond), if the inner surface temperature is 155°C (answer in unit kilo Watt)

A 3 kg collar slides with frictionless along a vertical rod is shown in below Figure. The
spring is under-formed when the collar A is at the same elevation as point O. The collar is
released from rest at y1 = 0.4 m.
Determine the velocities of the collar as it first passes a) y2 = 0.0 m, and b) y3 = − 0.4m

Write the heat conduction equation (without flow in and out) in cartesian coordinates for the following case:
1. Steady-state, 1-D, without heat generation (2 points)
2.Transient, 1-D, without heat generation (2 points)
3.Transient, 3-D, with heat generation (3 points)
3. Write the three types of boundary conditions. (3 points)

state the reason why the flexibility influence coefficient of a non constrained multi-degree vibration is can not be determined

Foil Plates

Place foil plates on the Van de Graaf generator face down. When the generator is on, what happens to the plates? Repeat the experiment with the plates facing up. Do plates behave any different? If so, why? If not, why not? Explain your reasoning.

Please draw picture