An orange with an average mass of 0.20 kg and average specific heat of 3.70 kJ/kg.SYMBOL 176 \f "Symbol"C is cooled from 20°C to 5°C. The amount of heat transferred from the orange is
A)7.4 kJ
B)24.8 kJ
C)18.5 kJ
D)55.5 kJ
E)11.1 kJ

Question

Quizplus · Accepted Answer

Solved by EES Software. Solutions can be verified by copying-and-pasting the following lines on a blank EES screen. 
C=3.70 "kJ/kg.K"
m=0.2 "kg"
T1=20 "C"
T2=5 "C"
"Applying energy balance E_in-E_out=dE_system gives"
-Q_out = dU_system
dU_system=m*C*(T2-T1) "kJ"
"Some Wrong Solutions with Common Mistakes:"
-W1_Qout =C*(T2-T1) "Not using mass"
-W2_Qout =-m*C*(T2+T1) "adding temperatures"

An Orange with an Average Mass of 0