6. (a) Name a conductor, an insulator, a semiconductor, a ductile material and a brittle material.

(b) Why does a typical conductor show a relatively high electrical conductivity and a high ductility at room temperature? Comment on its electrical conductivity when it is heated.

(c) Derive the units of ductility and electrical conductivity.

NASA has created a heat engine which operates between the sun and the vacuum of the space where the
temperature is absolute zero. He says that his engine is nearly 100% efficient. Do you agree with the claim
assuming the engine to be totally reversible? Analyse the scenario using equation for efficiency of Carnot
engine and Kelvin statement to evaluate your conclusion.

) A 50 mm-diameter propeller was installed in a 150 mm-diameter water pipe and the propeller speed was measured for a range of water discharge in the pipe. The water had a density and dynamic viscosity of 1000 kg/m³ and 0.00112 Ns/m² respectively. The measured results were as follows:

Plot the dependence of propeller coefficient against propeller Reynolds number. A geometrically similar propeller with diameter 100 mm was installed in a 300 mm-diameter pipe conveying oil with density 800 kg/m³ and dynamic viscosity 0.007 Ns/m² . Estimate the discharge in the oil pipe for measured propeller speeds of 40 rps and 90 rps.

Air at 20°C and 1 atm flows over a spherical object at 1 m/s. The sphere has a diameter of 10mm and its initial temperature is 134°C. If the density, specific heat, and conductivity of the sphere are 7832 kg/m”, 549 J/kg.K, and 49.2 W/m.K, respectively, calculate the temperature at the center of the sphere after 100 seconds.

The whey obtained from centrifugation to extract some proteins is stored in a preliminary tank and subsequently pumped at a rate of 20 L / s to the general storage tanks, to be used in other processes. The starting tank and the storage tank are kept at atmospheric pressure and the difference of 10 m in height that exists between the whey in each tank is constant. The total length of pipe in the suction line is 5 m with a standard 4-inch diameter and absolute roughness equal to 0.00125 m. The discharge length is 25 m with a diameter of 6 in and the same roughness. Consider the vapor pressure of the whey similar to that of water at 30 ° C (4243 Pa).

The density of the whey at operating conditions is 1027 kg / m3
The viscosity of the whey can be considered 0.0012 Pa * s.
The valves and accessories that are installed in the system's piping system are:
Accessory type

Resistances (K) for each accessory

2 Standard 90 ° elbows = 0.75

1 gate valve at the pump outlet = 0.17

1 globe valve fully open at the pump inlet = 10

Centrifugal tank inlet to pipeline = 0.5

Inlet from storage tank to pipeline = 0.6

Determine the following parameters:
a) Fluid velocity in the piping system (suction and discharge)
b) Energy losses due to friction in pipes (suction and discharge)
c) Reynolds number (suction and discharge).
d) Value of the friction factor (suction and discharge).
e) Friction energy losses in valves and accessories (suction and discharge).
f) Determine the NPSH available and required for the system
g) Pressure drop in the system.
h) Dynamic load of the system that the pump must deliver to propel the fluid from section A to section B shown in the figure.
i) The power received by the liquid, supplied by the pump.
j) The motor power, considering an efficiency of the motor-pump set of 60%.

A solid shaft is designed to twist no more than an angle of 2º when subjected to a torque of 800 Nm. The shaft is 1 m long and made from a material that has a shear modulus, G = 70 GN/m². Select an appropriate minimal diameter for the design specifications if

1. Solid shaft was used.
2. Hollow shaft of wall thickness 5mm was used.
3. If the shaft is to rotate at 2000 rpm, determine the maximum power that can be transmitted by the HOLLOW shaft.

1. Hot forging is used to reduce a metallic cylindrical workpiece with a diameter of 12 cm and height of 24 cm to a height of 15 cm. The coefficient of friction of the open die plate with the workpiece is 0.18 and the process takes 4 seconds to complete and at a constant speed. The strength coefficient of the workpiece C= 180 MPa and strain rate sensitivity exponent m = 0.25. calculate the following:

1. The forging shape factor at the end of the process.
2. The maximum flow stress (MPa).
3. The maximum forging force (N).
4. The power (W) required to complete the process.

3. In a Rankine cycle, the water enters the turbine at a pressure of L = 15 MPa and M = 525 ° C. Condenser pressure is N = 10 kPa. At the condenser outlet, it is assumed that the water is saturated liquid and the pump inlet pressure is again N = 10 kPa. Since the isentropic efficiency of the pump is Y 80%, the isentropic efficiency of the turbine is Z = 60%,
a-) Calculate the heat given to the loop in the boiler. (10 s)
b-) Calculate the net work of the loop. (10 s)
c-) Find the thermal efficiency of the loop. (10 s)

Air enters the diffuser of a turbojet engine at 18 kPa, 216 K, with a volumetric flow rate of 230 m³/s and a velocity of 265 m/s. The compressor pressure ratio is 15, and its isentropic efficiency is 87%. Air enters the turbine at 1560 K and the same pressure as at the exit of the compressor. The turbine isentropic efficiency is 89%, and the nozzle isentropic efficiency is 97%. The pressure at the nozzle exit is 18 kPa. Use an air-standard analysis.

a)

Determine the rate of heat input to the combustor, in MW.

Cryogenic engineering.

Theoretically investigate the performance of zeiner liquefaction system using inline helical and spherical tube arrangements...
Model the system and list all the variables related to it....Also study the efffect of varying outside conditions and inside conditions...

validate the results using scilab and Fortran 77...

please answer if u can otherwise skip it
don't waste my question quota....please

function and working principle of the component of the hydraulic power steering system with diagram. and kindly it's good if you send me a pdf or a book that briefly explains

7 mm çaplı 26 mm uzunluğundaki çelik tel, ön gerilmeli beton üretiminde kullanılmaktadır. P çekme kuvveti uygulandığında, telin 65 mm uzadığı görülmektedir. E=200 GPa olduğuna göre, a) P kuvvetinin büyüklüğünü b) telde oluşan gerilmeyi hesaplayınız. (7X2=14p)

a-Calculate conventional yield effort at 0.2% (0.002 in./in.)

b- Tensile strength.
c- The modulus of elasticity.
d- Elongation
e- The reduction in area.
f- The engineering effort to fracture
g- The real stress to fracture
h- The modulus of resilience

Magnesium

- Initial diameter of the test tube: 12 mm
- Initial calibrated length: 30 mm
- Calibrated length after fracture: 32.61 mm
- Diameter after fracture. 11.74 mm