Answer:
Compression ratio(r)
Explanation:
Otto cycle:
Otto cycle is an ideal cycle for all working petrol engine.It have four processes in which two are constant volume process and other two are reversible adiabatic or we can say that isentropic processes.All petrol engine works on Otto cycle.
The efficiency of Otto cycle given as follows
[tex]\eta =1-\dfrac{1}{r^{\gamma-1}}[/tex]
Where r is the compression ratio and γ is heat capacity ratio.
So from above we can say that the efficiency of Otto cycle depends onl;y on compression ratio (r).