ABSA 4B POWER ENGINEERING EXAM QUESTIONS WITH CORRECT VERIFIED ANSWERS | 100% PASS (A+ CERTIFIED)

ABSA 4B POWER ENGINEERING EXAM QUESTIONS WITH CORRECT VERIFIED ANSWERS | 100% PASS (A+ CERTIFIED)Dry-bulb temperature is a) the absolute temperature corresponding to the atmospheric pressure b) the dewpoint temperature c) not required to find the relative humidity d) the temperature of the air measured with an ordinary thermometer e) the same as the wet-bulb temperature if the relative humidity is less than 100% Answer D Wet-bulb temperature is a) the temperature indicated by a thermometer having its bulb covered by a water-wetted wick or cloth and the wet bulb is exposed to a rapidly moving stream of air b) the same as the dry-bulb temperature if the relative humidity is less than 100% c) the dewpoint temperature d) always less than the dry bulb temperature e) not required to find the relative humidity Answer A What is wet-bulb depression? a) lowering of the thermometer bulb into water b) sum of the wet-bulb temperature and the dry-bulb temperature c) decrease in relative humidity d) difference between the dry-bulb temperature and the wet-bulb temperature e) decrease in the absolute humidity Answer D Psychrometers are a) instruments used to determine the purity of air b) meters used to measure air speed c) meters used to measure the density of air d) instruments used to measure atmospheric pressure e) instruments used to determine the relative humidity of air Answer E Which of the following instruments use a battery-operated fan to draw air over the thermometer bulbs? a) hydrometer b) aspirating psychrometer c) sling psychrometer d) dry psychrometer e) potentiometer Answer B The specific volume of air is a) the volume of 1 kg of air at atmospheric pressure expressed in cubic centimetres b) the volume of 1 gram of air at atmospheric pressure expressed in cubic metres c) the volume of 1 kg of air at atmospheric pressure expressed in cubic metres d) the volume of 1 kg of air at any pressure e) the volume of 1 gram of air occupied at any temperature and pressure Answer C Standard air is a) the volume of 1 kg of air at 15 degrees Celsius and 100 kpa b) the mass of 1 cubic metre of air at atmospheric conditions c) the volume of 1 kg of air at ambient temperature and atmospheric pressure d) the volume occupied by 1 kg of dry air at 21 degrees Celsius and atmospheric pressure at sea level or 101.325 kpa e) the mass of 1 cubic metre of dry air at 20 degrees Celsius and atmospheric pressure Answer D Enthalpy of air depends on a) the pressure, temperature, and relative humidity of the air b) the relative humidity of the air only c) the pressure and temperature of the air only d) the air velocity e) the temperature of the air only Answer A