According to Newton's Law of Cooling, the rate of heat loss is proportional to the temperature difference between the object and its surroundings. While the initial temperature difference is the same (95-48 = 47°C and 71-24 = 47°C), the average temperature of the cup in Churu throughout its cooling process (from 95°C to 48°C) is significantly higher than the average temperature of the cup in Shimla (from 71°C to 24°C). Heat loss also occurs via radiation, which is proportional to the fourth power of the absolute temperature (Stefan-Boltzmann Law). The higher absolute temperature of the cup in Churu results in a faster rate of heat loss overall compared to the cup in Shimla, causing it to reach its room temperature (48°C) faster.
On a specific day and time temp. was 48 degree C in churu and 24 C in Shimla, Two metallic cups identical in all respects contained water at 95 degree C in churu and 71 Degree in shimla. Which one of these two cups reached room temp. first:
Asked in RPSC RAS Prelims 2008 · Topic: Heat and Thermodynamics (Modes of Heat Transfer (Conduction, Convection, Radiation))
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