A-LEVEL PHYSICS: 11.2.6: Comparing Petrol & Diesel Engines (SaveMyExams)

Question 1

diesel engines are more ___ than petrol engines, and this can be seen from their ___ ___

Answer 1

efficient, indicator diagrams

Question 2

___ engines are more efficient than ___ engines, and this can be seen from their ___ ___

Answer 2

diesel, petrol, indicator diagrams

Question 3

efficiency is directly proportional to the compression ratio of an engine, which is defined as:

Answer 3

volume enclosed at beginning of compression stroke / volume enclosed at end of compression stroke

Question 4

a diesel engine can achieve a much higher ___ ___ than a petrol engine. this is an indication that diesel engines are more…

Answer 4

compression ratio, efficient

Question 5

why do diesel engines require higher compression ratios then petrol engines?

Answer 5

to get the pressure and temperature of the air high enough for the diesel fuel to self-ignite

Question 6

why are diesel engines more expensive to produce than petrol engines?

Answer 6

because they operate at higher pressures, so need to be built more robust

Question 7

petrol engines produce more … than diesel engines: (3)

Answer 7

-carbon dioxide
-carbon monoxide
-hydrocarbons