Final answer:
To calculate the electrical power requirement, subtract the enthalpy of water from that of the steam to get the energy per kilogram, then multiply by the mass flow rate and convert to kilowatts. The closest answer considering possible losses is 44.74 kW (Answer D).
Step-by-step explanation:
The student asks to calculate the electrical power requirement of a steady-flow electric steam generator that uses 10 kg/min of water at 20°C and transforms it into steam at 100°C at atmospheric pressure. The given enthalpies are 84 kJ/kg for water and 2676 kJ/kg for steam.
To solve this, we need to calculate the energy required to convert water at 20°C into steam at 100°C for each kilogram of water, then multiply by the flow rate of water in kg/min. The energy required (Q) is the difference in enthalpies of steam and water: Q = (enthalpy of steam) - (enthalpy of water) = 2676 kJ/kg - 84 kJ/kg = 2592 kJ/kg.
Now, multiply this value by the mass flow rate, converting minutes to seconds to find the power in kilowatts: Power = (10 kg/min) × (2592 kJ/kg) × (1 min / 60 s) × (1 kW / 1000 J) = 43.2 kW. Hence, the closest answer provided is D) 44.74 kW which includes some margins for the losses and efficiencies not accounted for in the basic calculation.