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IC engines (SI/petrol): typical compression ratio range For conventional petrol (spark-ignition) engines, select the typical compression ratio range used in practice. Choose the correct range.

Q: IC engines (SI/petrol): typical compression ratio range For conventional petrol (spark-ignition) engines, select the typical compression ratio range used in practice. Choose the correct range.

Concept SI (petrol) engines commonly operate with compression ratios ≈ 6:1–10:1. Among the given ranges, 5 to 8 best fits standard textbook values and avoids knock for regular fuels. Final Answer 5 to 8

Difficulty: Easy

3 to 6
5 to 8
15 to 20
20 to 30

Correct Answer: 5 to 8

Explanation:

Concept
SI (petrol) engines commonly operate with compression ratios ≈ 6:1–10:1. Among the given ranges, 5 to 8 best fits standard textbook values and avoids knock for regular fuels.

Final Answer
5 to 8

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