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What is Specific Heat Capacity?

The specific heat of a substance is the quantity of heat required to raise the temperature of 1-kilogram mass of the substance through 1Kelvin.

The specific heat capacity of the material is a physical attribute. Itis also an instance of a substantial property since its value is directly proportional to the magnitude of the system being analyzed.

Mathematical Form {Formula/equation}

Ordinarily, each time a body is heated, its temperature increases. An increase in the temperature of a body is found to be proportional to the amount of heat absorbed by it. It has also been observed that the quantity of heat ∆Q required to raise the temperature ∆T of a body is proportional to the mass m of the body. Thus the equation is,

ΔQ∝mΔT

Or

ΔQ=c mΔT

This ∆Q is the quantity of heat absorbed by the body and c is the constant of proportionality referred to as the specific heat capacity or simply specific heat.

Thus, the specific heat of a material formula is

c= ΔQ/mΔT

Explanation of equation

The dependence of specific heat upon temperature and mass are understandable. As the kinetic energy of an atom or molecule is proportional to temperature, so the internal energy is directly proportional to the total temperature and the range of molecules or atoms.

Since the absorbed heat is equivalent to the shift in the internal energy, so heat is proportional to the mass and change of temperature of the body.

The transferred heat depends upon the substance in order, as an instance, the heat required to raise the temperature will be not the same for alcohol compared to water. For the same substance, the ∆Q also be contingent upon the phase (gas, liquid, or solid).

SI Units of Specific Heat Capacity

In SI units, mass is measured in kilograms (kg), heat ∆Q is measured in joule (J) and temperature increase ∆T is measured in kelvin (K). Thus, the SI unit of specific heat is joule per kelvin per kg (J/K/kg, J/ (kg K), Jkg-1K-1.

Significance of large Specific Heat Capacity of Water
  • The specific heat of water is 4200 Jkg-1K-1and of soil is all about 8 10 Jkg-1K-1. Because of this the temperature of soil would increase five times more than compared to the exact same mass of water at precisely the same amount of heat. Thus, the temperature of land rises and falls more rapidly than that of the sea.

Hence, the temperature variations from summer to winter are much smaller at places near the sea than land far away from the sea. For instance, as you can observe in Karachi.

 

  • The heat capacity of water contains a fantastic deal regarding controlling extremes in the environment. As an example, the fish from seas and ponds are joyful because the heat capacity of water at the pond usually means the temperature of this water tends to always be relatively the same from day to night time. They don’t really need to be worried about turning to the air conditioner or putting on warm clothes.

 

  • Water comes with large specific heat capacity. It is very helpful in preserving and carrying thermal energy because of the high specific heat capacity.
  • The cooling system of automobiles utilized water to remove undesirable thermal energy. In a Vehicle, a large quantity of heat is produced by its own engine due to which temperature keeps on rising.

Specific Heat1

The engine will cease unless it is not cooled down. Water circulating across the engine keeps regulating temperature. Water absorbs undesired thermal energy of this engine and dissipates heat through its radiator.

 

  • In the central heating system, hot water can also be used to transmit thermal energy through pipes from boilers to radiators. These radiators are mended at suitable places within houses.

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Specific Heat Capacity of a few common substances