Summary

• Description:

  The PDF document comprises Form 3 Physics notes on the topic of Quantity of Heat.

  The topics and sub-topics covered in the document include:

  • Introduction to Heat
    • Heat is defined as a form of energy that flows from one body to another due to a temperature difference between them.
  • Heat Capacity and Specific Heat Capacity
    • Heat Capacity (C): Defined as the quantity of heat needed to raise the temperature of a given mass of a substance by one degree Celsius or one Kelvin. The formula is given as C = Q/θ.
    • Specific Heat Capacity (c): Defined as the quantity of heat required to raise the temperature of 1 kg of a substance by 1°C or 1 K. The formula is Q = mcθ.
    • A worked example is provided to demonstrate the calculation of the quantity of heat supplied by a heater, the heat capacity of a metal block, and its specific heat capacity.
  • Latent Heat
    • Fusion: This is the process of changing a substance from a solid to a liquid without a change in temperature.
    • Specific Latent Heat of Fusion (L_f): This is the quantity of heat needed to completely change 1 kg of a substance from solid to liquid at its melting point. The formula is Q = mL_f. Factors affecting the melting point, such as pressure and dissolved substances, are also mentioned.
    • Specific Latent Heat of Vaporization (L_v): This is the quantity of heat required to change 1 kg of a liquid at its normal boiling point into a vapour without a change in temperature. The formula is Q = mL_v. A worked example is included to estimate the specific latent heat of vaporization for steam.
  • Evaporation
    • The notes list the factors that affect the rate of evaporation, which are temperature, surface area, draught (air movement), and humidity.
    • A table compares the processes of boiling and evaporation, highlighting differences in the temperature at which they occur and the effect of atmospheric pressure.
    • An application of cooling by evaporation, such as sweating, is mentioned.

  These notes are comprehensive, neat, and printable, making them an excellent resource for students studying the concepts of heat capacity and latent heat. They are also highly suitable for teachers to use for lesson preparation, providing clear definitions, formulas, and worked examples to reinforce understanding.

• File Size:

  200.37 KB
• Length:

  8 pages
• Category:

  Lesson Notes
• Level:

  Form 3
• Subject:

  PHYSICS
• Posted By:

  Caleb_Peter

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