Question

Cata motorina a consumat un motor Diesel cu randamentul de 28% si puterea utila de 75 kW daca el a functionat timp de 1h......raspunsul ≈22 kg

Answer 1

η=$\frac{Pu}{Pc}$⇒Pc=$\frac{75 kW}{ \frac{28}{100} }$= 267,9 kW
Pc=$\frac{L}{timp}$⇒L= 267,9 kW * 1h= 267,9 kW * 3600 s=964440 J
q (putere calorica)=$\frac{Q}{m}$⇒m= $\frac{Q}{q}$= $\frac{964440 J}{46000000 J/kg}$= 0,02 kg