Two parallel disks which are separated by a distance of 25 cm are enclosed in a large evacuated chamber that is at -250 c temperature. the larger disk is 50 cm in diameter, is at 800 c, and has an emissivity of 0.6. the smaller disk is 25 cm in diameter, is at 400 c temperature, and has an emissivity of 0.4. calculate the radiative power lost by the large disk. hint: note that the disks lose heat from both sides.

Water in a partially filled large tank is to be supplied to the roof top, which is 8 m above the water level in the tank, through a 2.2-cm-internal-diameter pipe by maintaining a constant air pressure of 300 kpa (gage) in the tank. if the head loss in the piping is 2 m of water, determine the discharge rate of the supply of water to the roof top in liters per second.

Slip occurs via two partial dislocations because of (a) the shorter path of the partial dislocation lines; (b) the lower energy state through partial dislocations; (c) the charge balance.

An ideal otto cycle with air as the working fluid has a compression ratio of 8. the minimum and maximum temperatures in the cycle are 300 k and 1340 k. use constant specific heats at room temperature to determine (a) the amount of heat transferred to the air during the heat- addition kj/kg, (b) the thermal efficiency, and (c) the thermal efficiency of a carnot cycle ope limits. process, in rating between the same temperature