Heat ↔ Temperature
Q = mcΔT — same heat ≠ same ΔT (depends on c).
Key Notes
HEAT (Q) and TEMPERATURE (T) are different physical quantities.
TEMPERATURE: average kinetic energy of molecules (a measure, like 'velocity').
HEAT: energy transferred due to temperature difference (a flow, like 'distance').
Heat flows SPONTANEOUSLY from hot to cold body — equilibrating temperatures.
Units: Q in joules (J) or calories (1 cal = 4.184 J). T in Kelvin or Celsius.
Specific heat capacity c: heat needed per kg per K. Q = m·c·ΔT.
Water has very high c (~4186 J/kg·K) — that's why oceans moderate climate.
Heat capacity C = m·c — heat needed to raise the WHOLE body by 1 K.
Body temperature depends on how heat is shared among DEGREES OF FREEDOM (equipartition theorem).
Formulas
Heat-temperature relation
Heat needed to change temperature by ΔT.
Heat capacity
Total heat to raise whole body by 1 K.
Specific heat of water
Reference value; very high.
Calorie conversion
Useful for nutritional calorie comparisons.
Important Points
Heat is ENERGY FLOW; temperature is STATE.
When you say 'this body has heat', it's loose language — bodies have INTERNAL ENERGY, transfer HEAT.
Water's high c means it heats and cools slowly — oceans absorb huge heat without much T change.
Same Q applied to two materials: smaller c ⇒ larger ΔT.
Specific heat depends on the SUBSTANCE; heat capacity depends on AMOUNT plus substance.
Calorie (small c) is energy unit. Calorie (capital C) is 1000 cal — used for food labels.
Heat ↔ Temperature notes from sciphylab (also known as SciPhy, SciPhy Lab, SciPhy Labs, Physics Lab). Class 11 physics revision for JEE Mains, JEE Advanced, NEET UG, AP Physics 1/2/C, SAT, and CUET-UG.