In an air-standard Otto cycle, the compression ratio is

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In an air-standard Otto cycle, the compression ratio is 10. The condition at the beginning of the compression process is 100 kPa and 27°C. Heat added at constant volume is 1500 kJ/kg, while 700 kJ/kg of heat is rejected during the other constant volume process in the cycle. Specific gas constant for air = 0.287 kJ/kgK. The mean effective pressure (in kPa) of the cycle is

1. 103
2. 310
3. 515
4. 1032

Correct Option: D

Here, P₁ = 100 kPa
T₁ = 27°C

	V₄	=	V₁	= 10
	V₃		V₂

C_v = 0.287 kJ/kgK
P_m × (V₁ – V₂ )= work done
= h₁ – h₂
= 1500 – 700 = 800 kJ
Now P₁V₁ = mRT₁
or 100 × 10³ × V₁ = 1× 0.287 × 10³ × 300
or V₁ = 0.861
∴ V₂ = 0.0861
Now P_m (0.861 – 0.0861) = 800
∴ P_m = 1032 kPa