Answer:
Otto engine Diesel engine
1.Works on Otto cycle 1.Works on diesel cycle.
2.Petrol use a fuel. 2.Diesel use as a fuel.
3.Heat addition at constant volume. 3.Heat addition at constant pressure.
4.Light in weight 4.Heavier in weight.
5.Low compression ratio 5.High compression ratio.
6.Low thermal efficiency 6.high thermal efficiency.