Chapter- Thermal energy

Equation

• Specific Heat Capacity: Q = mcΔT

  • Q: Change in thermal energy (J)

  • m: Mass of the substance (kg)

  • c: Specific heat capacity of the substance (J/kg°C)

  • ΔT: Change in temperature (°C)

• Conduction: Q = kAΔTΔx/L

  • Q: Heat transferred (J)

  • k: Thermal conductivity of the material (W/mK)

  • A: Cross-sectional area of the material (m²)

  • ΔT: The temperature difference between the hot and cold ends (°C)

  • Δx: Thickness of the material (m)

  • L: Length of the material (m)

    
    
    
    

• Convection: Q = hAΔT

  • Q: Heat transferred (J)

  • h: Convection heat transfer coefficient (W/m²K)

  • A: Surface area of the object (m²)

  • ΔT: The temperature difference between the object and the surrounding fluid (°C)

• Radiation: Q = σAε(T₁⁴ - T₂⁴)

  • Q: Heat transferred (J)

  • σ: Stefan-Boltzmann constant (5.67 x 10⁻⁸ W/m²K⁴)

  • A: Surface area of the object (m²)

  • ε: Emissivity of the object (dimensionless)

  • T₁: Absolute temperature of the object (K)

  • T₂: Absolute temperature of the surroundings (K)

• Calorimetry: Q₁ + Q₂ = 0

  • Q₁: Heat gained by one object (J)

  • Q₂: Heat lost by another object (J)

• Ideal Gas Law: PV = nRT

  • P: Pressure of the gas (Pa)

  • V: Volume of the gas (m³)

  • n: Number of moles of gas (mol)

  • R: Gas constant (8.314 J/mol·K)

  • T: Absolute temperature of the gas (K)