Prabin Kalikote

We know that mercury is only the metal that exists inthe state of liquid with a freezing point - 39C andboiling point 357C. The range of its FP and BP is suitablefor measuring normal temp. It is also a goodconductor of heat. It has a low specific heat capacity i.e.140 J/KgC.So, it is usedas a thermometric liquid.

We know that in the desert the land is covered all by sand.Sand has low specific heat capacity which means it gainsand loses heat very fast. So, during the day it gains max heat and becomes hotter and during the night it loses all the heat and becomes very cold.

We all know that, the temperature of our body higher in the bedroom than the temp. of surrounding. So, when we gooutside, our body loses the heat and we feel cold.

After strolling outside in open air the temp of ourbody again decreases below the temp. of bedroom. So, when we come back to the bedroom, our body gains heat and we feel warm.

We know that the density of solid ghee is more than thatof liquid or hot ghee. So while freezing, all the frozenghee starts to displace to the bottom. But, water has a higherdensity at 4⁰C than at 0⁰C. It means water has a higherdensity than ice. So, while freezing, ice displaces tothe top.

As we all know that water has the highest specificheat capacity. It means that it has the highest capacity of absorbing heat. So, the heated water releases heatfor the longest time. As the hot bottles are used for heating purposes, hot water is used in them.

We know from the principle of calorimetry that the heatgained by a cool body from a hot body is equal to the heatlost by a hot body. To cool the engines, something shouldabsorb its heat and water has the highest capacityto absorb heat as its specific heat capacity 4200J/Kg⁰C.
So, water is used to cool the engines of machines.

Calorimetry is the measurement of heat lost orgained by an object.

The principle of calorimetry state that'When ahot body is mixed with a cold body, the heat lost bythe hot body is equal to the heat gained by thecold body, provided that no heat escapes to thesurroundings.'

Therefore, Heat lost = Heat gained.