If an automobile engine is overheated, it is cooled by pouring water on it. It is advised that the water should be poured slowly with the engine running. Explain the reason.
Answers
Thermal stress generates which results in crack in engine parts
Explanation:
There are two reason not to pour the cool water speedily on a running engine, which are describe below:-
1. If an automobile engine is overheated, cool water should not be poured because thermal stress generates due to contraction on fast cooling and uneven crack form in the engine parts, it may reduce the life of engine.
And another concepts to be know that cylinder head and block are made of alminium and cast iron and their coefficient of expansion is different so the expansion in head and block will be different, it results the uneven gap between head and cylinder block which may results in the leakage of fuel, so it is advised that the water should be poured slowly with the engine running.
2. If you pour cool water speedily on a running engine the water will convert in hot steam and it can scald you.
The Reason is Thermal Stress
Explanation:
As we know, water is needed and being put up in an overheated engine a bit slowly but carefully.
Two reasons for the same, which are-
1.) Avoiding Cracking Down of Engine
2.) Safety
There could be an uneven thermal contraction in the engine parts owing to the rapid cooling of overheated parts of the engine.
Which results in,
a.) Thermal Stress being Developed
b.) Head/Block may cracken up owing to Potential Cracking
Severe burns may develop due to overheated engine, by the cold water being put up by Blowback Pressure.