Energy needed to raise one kilogram by one kelvin.
c is energy needed to raise 1 kg by 1 K: Q=mcΔT. For gases c_p (constant pressure) exceeds c_v by R, and γ=c_p/c_v (1.4 for air). Water has high c_p (4.18 kJ/kg·K), making it an excellent coolant and thermal store.
Heating 2 kg water by 30 K takes 251 kJ.
Specific heat tells you how much energy a material stores per degree of temperature rise, which sets heating and cooling times.
Energy needed to raise one kilogram by one kelvin.
Specific heat tells you how much energy a material stores per degree of temperature rise, which sets heating and cooling times.
Its hydrogen bonds absorb energy, so water needs much more energy than most liquids for the same temperature rise.
It varies with temperature, and for gases it depends on whether pressure or volume is held constant.
Typical applications include estimating the energy to heat water in a kettle, comparing the heat storage of water and oil in a thermal store and sizing a heater for a metal part that must reach a set temperature.
Study "Pressure" first (topic 6 of 105 in Thermodynamics & Fluids). It covers the groundwork this topic builds on.
c_p-c_v=R for ideal gas. Latent heat is separate. c varies with temperature.
Heating 2 kg water by 30 K takes 251 kJ.
The next topic is "Heat and work", which builds directly on this one.
It is classed as Beginner in Thermodynamics & Fluids (topic 7 of 105). It is an entry-level topic. It relies only on basic school mathematics and the ideas introduced earlier in this discipline.
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