Answer:
The rise in temperature after 15mins is (ΔT)=
°c
Step-by-step explanation:
The solution is obtained from energy balance;
W=M x Cv x ΔT
where;
W(workdone)=quantity of energy in joules
Workdone=Power x Time
Power=2kw
Time=15mins=15 x 60=900secs
Workdone=2 x 900=1800KJ
Cv=Specific heat capacity of air= 0.718 kJ/kg.K
M=Mass of air=80kg
ΔT= change in temperature in °C
therefore;
ΔT=

ΔT=

ΔT=

ΔT=
°c