Heat: Energy that moves from a hot object to a cold one. (उष्णता: गरम वस्तूपासून थंड वस्तूकडे जाणारी ऊर्जा)
Temperature: How hot or cold something is. (तापमान: वस्तू किती गरम/थंड आहे हे दर्शवणारी संख्या)
Specific Heat: Heat needed to increase temperature of 1 kg of a substance by 1°C. (विशिष्ट उष्णता: 1 किग्र. पदार्थाचे तापमान 1°C वाढवायला लागणारी उष्णता)
Latent Heat: Heat used to change state without changing temperature. (गुप्त उष्णता: स्थिती बदलण्याकरिता लागणारी पण तापमान न वाढवणारी उष्णता)
📐 Useful Formulas
Concept
Formula
Units
Heat
Q = mcΔT
Joules (J)
Latent Heat
Q = mL
Joules (J)
Boyle’s Law
P₁V₁ = P₂V₂
atm, L
Charles’s Law
V₁/T₁ = V₂/T₂
L, K
Combined Gas Law
(P₁V₁)/T₁ = (P₂V₂)/T₂
-
Kelvin Conversion
K = °C + 273
K
🔑 Important Words
Boiling Point (सालनांक)
Melting Point (गलनांक)
Evaporation (बाष्पीभवन)
Condensation (संघनन)
Thermal Expansion (उष्ण विस्तार)
Calorimetry (तापमापन प्रक्रिया)
Sublimation (थेट वायुरूपात रूपांतर)
Sensible Heat (महसूस होणारी उष्णता)
📏 Gas Laws – Definitions and Usage
Boyle’s Law: At constant temperature, the pressure of a gas is inversely proportional to its volume. (स्थिर तापमानास, दाब आणि आयतन एकमेकांशी व्यस्त प्रमाणात असतात) Use when: Temperature is constant and pressure or volume is changing.
Charles’s Law: At constant pressure, the volume of a gas is directly proportional to its temperature (in Kelvin). (स्थिर दाबात, वायूचे आयतन तापमानाशी (Kelvin मध्ये) समप्रमाणात असते) Use when: Pressure is constant and you are comparing volume and temperature.
Gay-Lussac’s Law: At constant volume, the pressure of a gas is directly proportional to its temperature (in Kelvin). (स्थिर आयतनात, वायूचा दाब तापमानाशी समप्रमाणात असतो) Use when: Volume is constant and pressure or temperature changes.
Combined Gas Law: Combines Boyle's, Charles's and Gay-Lussac's laws into one equation: (P₁V₁)/T₁ = (P₂V₂)/T₂ (तीनही नियम एकत्र करून वापरणारा नियम) Use when: All three—pressure, volume, and temperature—are changing.
Ideal Gas Law (not in formula table): PV = nRT (सिद्ध वायू नियम: वायूचे वर्तन दर्शवणारा संपूर्ण सूत्र) Use when: You need to find moles, pressure, volume, or temperature of a gas.
🧠 Easy Tricks for MCQs
Memory Trick (HEAT): "Hi Everyone At Tea" → Heat, Evaporation, Absorption, Temperature