Four hundred grams of nitrogen gas (molecular weight = 28 g/mole) are stored in a 10-liter container. Set up an Excel worksheet to determine the pressure of the gas (in atmospheres) as a function of temperature and volume, assuming nitrogen is an ideal gas. Place the value of each variable in its own cell. Label all of the quantities clearly. Recall that the ideal gas law is PV=nRT where P = pressure (atmospheres) V = volume (liters) n = number of moles (mass of gas/molecular weight) R = ideal gas constant (0.082054 liter atm/mole K) T= absolute temperature (°K = °C + 273) (a) What pressure in atm corresponds to a temperature of 17.5°C?

The mass flow rate of the fluid remains constant in all steady flow process. a)- true b)- false

Aloaded platform of total mass 500 kg is supported by a dashpot and by a set of springs of effective stiffness 72 kn/m. it is observed that when the platform is depressed through a distance x = 12.5 cm below its equilibrium position and then released without any initial velocity; it reaches its equilibrium position in the shortest possible time without overshoot. find the position and velocity of the loaded platform 0.10 sec. after its release. if a further load of 400 kg is added to the platform, find, i) the frequency of damped vibrations, and i) the amplitude of vibration after 2 complete oscillations, given that the initial amplitude is 15 cm.

Air is to be cooled in the evaporator section of a refrigerator by passing it over a bank of 0.8-cm-outer-diameter and 0.4-m-long tubes inside which the refrigerant is evaporating at -20°c. air approaches the tube bank in the normal direction at 0°c and 1 atm with a mean velocity of 4 m/s. the tubes are arranged in-line with longitudinal and transverse pitches of sl- st 1.5 cm. there are 30 rows in the flow direction with 15 tubes in each row. determine (a) the refrigeration capacity of this system and (b) pressure drop across the tube bank. evaluate the air properties at an assumed mean temperature of -5°c and 1 atm. is this a good assumption?