EGR_102_Lecture_HW_01_Solution-1

EGR_102_Lecture_HW_01_Solution-1 - EGR 102 Lecture HW 01...

This preview shows pages 1–2. Sign up to view the full content.

EGR 102 of 4 pages Lecture HW 01 1 EGR 102 Lecture HW 01 Due at beginning of lecture on Friday, January 20 4 Problems, 4 Points Each, 16 Points Total Name: Solution PID: Problem 1 (4 pts): A group of 30 students attend a class in a room that measures 10m by 8m by 3m. Each student takes up 0.075 m 3 and gives out 80W of heat (1W = 1 J/s). Calculate the air temperature rise during the first 15 minutes of the class if the room is completely sealed and insulated. Assume heat capacity, C v , for air is 0.718 kJ/(kg K). Assume air is an ideal gas at 20°C and 101.325 kPa. Note that the heat absorbed by the air Q is related to the mass of the air m , the heat capacity, and the change in temperature by the following relationship: Q = mC v (T 2 -T 1 ) The mass of the air can be obtained from the ideal gas law: PV = mRT / Mwt Where P is the gas pressure, V is the volume of the gas, Mwt is the molecular weight of the gas (for air, 28.97 kg/kmol), and R is the ideal gas constant [8.314 kPa m 3 /(kmol K)]. kJ

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Page1 / 4

EGR_102_Lecture_HW_01_Solution-1 - EGR 102 Lecture HW 01...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online