Ch 11 covers temperature measurement, thermal expansion, specific heat, calorimetry, change of state, and the three modes of heat transfer — conduction, convection, and radiation.
Temperature scales: Celsius, Fahrenheit, Kelvin (T_K = T_C + 273.15). Thermal expansion: linear (ΔL = αLΔT), area (ΔA = 2αAΔT), volume (ΔV = 3αVΔT). Water anomalous expansion: contracts from 0-4°C, expands above 4°C (lakes freeze from top).
Q = mcΔT (c = specific heat capacity). Calorimetry: heat lost = heat gained (thermal equilibrium). Change of state: solid→liquid (fusion, latent heat L_f), liquid→gas (vaporisation, L_v). During change of state, temperature remains constant. For water: L_f = 334 J/g, L_v = 2260 J/g.
Conduction: through material without bulk movement, Q/t = KA(T₁−T₂)/L. Convection: through fluid movement (natural: density difference; forced: fan/pump). Radiation: electromagnetic waves, no medium needed. Stefan-Boltzmann law: E = σAT⁴. Wien's displacement law: λ_max × T = constant. Greenhouse effect: CO₂ traps infrared radiation.
Download: https://ncert.nic.in/textbook/pdf/keph203.pdf | Part II: https://ncert.nic.in/textbook/pdf/keph2ps.zip
Water has an anomalous property: it is densest at 4°C. As air temperature drops, surface water cools below 4°C and becomes less dense, so it stays on top and eventually freezes. The warmer (4°C) denser water stays at the bottom, allowing aquatic life to survive below the ice.
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