FUNDAMENTALS OF MOMENTUM, HEAT AND MASS TRANSFER COMPREHENSIVE SOLVED QUESTIONS AND COMPLETE ANSWERS

FUNDAMENTALS OF MOMENTUM, HEAT AND
MASS TRANSFER COMPREHENSIVE SOLVED
QUESTIONS AND COMPLETE ANSWERS

◉ The rating problem


The sizing problem
Answer: Rating: It deals with the determination of the heat transfer
per unit time for an existing system at a specified temperature
difference.


Sizing: It deals with the determination of the capacity of a system in
order to transfer heat at a specified rate for a specified temperature
difference.


◉ If the total energy entering a system (Ein) is 75 J and the total
energy leaving the system (Eout) is 15 J, then the change in the total
energy of the system (ΔEsystem) is _____.


90 J
60 J
5J
1125 J

, Answer: 60 J


◉ The specific heat at constant pressure is _____ the specific heat at
constant volume for a given system.


less than
not related to
equal to
greater than
Answer: greater than


◉ The differential changes in the enthalpy (h) of an ideal gas in
terms of specific heat at constant pressure cp can be given by _____.
Multiple choice question.


1dh1dh =cp dT
dh =1cp1cp dT
dh = cp dT
dh = (1 + cp) dT
Answer: dh = cp dT