Heat and Temperature

What is Heat?
Heat is a kind of energy associated with the molecular motion of matter that causes the sensation of cold or hot.
What is Temperature?
Temperature is an object's thermal state that determines whether it will gain or lose heat when it comes into thermal contact with another object.
State the difference between heat and temperature.
Heat Temperature
Heat is a form of energy. Temperature is the thermal state of a body.
Heat transfer does not depend on the quantity of heat. Heat transfer depends on the temperature.
The unit of measurement of heat is Joule. The unit of measurement of temperature is Kelvin.
What are thermal conductors?
Materials that can efficiently transfer heat through them are called thermal conductors.
What are thermal insulators?
Materials that resist the transfer of heat through them are called thermal insulators.
Why are metals much better thermal conductors than most other materials?
Metals have free electrons that can move between atoms. When heat is applied to a metal, these free electrons rapidly travel through the material, colliding with atoms along the way. This phenomenon enhances thermal conduction, facilitating faster heat transfer. In contrast, most non-metals lack free electrons. Consequently, heat conduction in non-metals occurs at a much slower rate compared to metals.

Temperature Scale

We use different scales to measure temperature. The three temperature scales widely used today are Celcius, Fahrenheit, and Kelvin. The mathematical relationship between these three scales is as follows:
TC 100 = TF - 32 180 = TK - 273.15 100

or, TC 5 = TF - 32 9 = TK - 273.15 5
Here, TC is temperature is celsius scale, TF is temperature is Fahrenheit scale, and TK is temperature is Kelvin scale.

What is Specific Heat?

The amount of heat required to raise the temperature of 1 kg of a substance by 1 kelvin is called the specific heat of that substance. It is denoted by small letter c or s in different books.

s = Q m ( T 1 - T 2 )

Latent Heat

Definition: Latent heat is the energy absorbed or released to change the state of matter without changing its temperature.

Challenge Yourself: Practice Problems to Solidify Concepts

  1. The highest officially recorded temperature in Bangladesh was 113.2°F on May 15, 1972.
    1. What is this temperature on the Celsius scale? Answer: 45.1°C
    2. What is this temperature on the Kelvin scale? Answer: 318.25K
  2. At what temperature is the Fahrenheit scale reading equal to
    1. Twice that of the Celsius scale? Answer: 320°F
    2. Half that of the Celsius scale? Answer: -12.3°F

Coefficient of Linear Expansion.