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Heat and Temperature — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsHeat and Temperature4 Marks
Question
If an automobile engine is overheated, it is cooled by putting water on it. It is advised that the water should be put slowly with engine running. Explain the reason.
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Answer

In a hot engine the hot parts are expanded because of heat, if cold water is poured suddenly then there will be uneven thermal contraction in the parts. This will result in a stress to develop between the various parts of the engine and may let the engine to crack down.

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