Rate of energy increase within the control volume is given by

A)
rate of energy inflow + rate of energy outflow
B)
rate of energy inflow – rate of energy outflow
C)
rate of energy inflow * rate of energy outflow
D)
rate of energy inflow / rate of energy outflow

Correct Answer : Option (B) :   rate of energy inflow – rate of energy outflow


Explanation : The rate of accumulation of energy within the control volume is equal to the net energy flow across the control surface.