Question

In: Physics

Heat flows from a reservoir at 373 K to a reservoir at 273 K through a...

Heat flows from a reservoir at 373 K to a reservoir at 273 K through a 0.39-m copper [thermal conductivity 390 J/(s

Solutions

Expert Solution

Rate of Heat trasfer per unit time is given by

R=       (where K is thermal conductivity of material , A is area , d is thickness and (T2 -T1) is temprature difference )

R=     

R=97 J/S

so heat transfer in 2.9 min

2.960=174 second

heat transffer in 174 sec= 97174 J

                                  =16878 J

and efficiency of carnot engine is

E=   

E=273-173/273

E=(0.366 100 ) %

E=36.6 %

heat not being used 63.4%

so heat unvailable for use =63.4% of 16878

                                 =10700.65J (ANS)


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