Heat_and_Temperature_Notes

Heat and Temperature

  • Heat: A form of energy measured in Joules (J); represents the total thermal energy in an object.

  • Temperature: Measures the average energy of particles in an object; indicates how hot or cold it is (°C).

Measuring Temperature

  • Temperature is measured using analogue or digital thermometers.

Heat Transfer

Conductors

  • Conductors: Materials that allow heat to pass through (e.g., metals).

Insulators

  • Insulators: Materials that resist heat flow (e.g., wood, plastic).

  • Heat moves from a hot region (higher temperature) to a cold region (lower temperature).

Factors Affecting Heat Transfer

  1. Temperature Difference: Greater difference = faster transfer.

  2. Surface Area: Larger surface area = faster transfer.

Thermal Equilibrium

  • Heat transfer continues until both objects reach the same temperature.

Methods of Heat Transfer

1. Conduction

  • Conduction: Heat transfer in solids by vibrating particles.

2. Convection

  • Convection: Heat transfer in liquids and gases through convection currents.

3. Radiation

  • Radiation: Heat transfer through empty space (vacuum) via electromagnetic waves.

Real-Life Example of Heat Transfer

  • Example: Cooking on a stove:

    • Conduction: Heat travels through the metal pan to the food.

    • Convection: Heat circulates through boiling water or hot air.

    • Radiation: Heat is emitted from the flame or electric coil.