Question

Un motor termic dezvolta o putere de 50 kW. Randamentul lui este de 30%. Cati litri de benzina a consumat el daca a functionat 10 ore?

Answer 1

η=$\frac{L}{Q}$
P=50 kW=50000 W
t=10 h=36000 s
P=$\frac{L}{t}$ =>L=P*t=1800000000 J =1,8 GJ
η=$\frac{L}{Q} \ \textless \ =\ \textgreater \ 0,30= \frac{1800000000}{Q} =\ \textgreater \ Q= \frac{1800000000}{0,30} =6000000000 J$=6000 MJ=6 GJ
q=$\frac{Q}{m}$
q=45,98 MJ
q=$\frac{Q}{m} \ \textless \ =\ \textgreater \ 45,98= \frac{6000}{m} =\ \textgreater \ m= \frac{6000}{45.98}=130, 491 l$