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PART - 2 CH - 9 Mechanical Properties of Fluids — Physics STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 SciencePhysicsPART - 2 CH - 9 Mechanical Properties of Fluids2 Marks
Question
When small drops of water are sprayed, why is cooling produced?
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Answer

Spraying in small drops increases the surface area. Therefore, there is an increase in the surface energy but in this work there is a decrease in the internal energy (because the total energy is conserved). Hence, the fall in temperature produces coolness, which we experience in daily life. Feeling more cold while bathing under a water fountain is an example of this.

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