What is Temperature? In our everyday life we all listen to a statement “Today the temperature is 23 degree Celsius or 23°C or some other value". Now have you ever asked yourself a question what exactly does temperature means? Let us understand it.


Maths class 3 Temperature


  • The intensity of the heat present in any body is known as temperature.


  • It is measured using an instrument called Thermometer.
  • The unit in which it is measured is Degree Celsius(°C) and the standard unit is Kelvin.(K)


Units and Conversions


There different units to measure the temperature and are listed below:

  1. Degree Centigrade or Degree Celsius – written as °C.
  2. Degree Fahrenheit - written as °F.
  3. Kelvin- written as K.

Kelvin is considered as the SI unit of temperature.


Temperature in degree Celsius = 273 - Temperature in Kelvin


Example 1: Convert 23°C into Kelvin.

Solution: 1°C = 273- Temperature in K

Therefore 1 Kelvin = 273 – 1°C = 272 K.


Conversion from Degree Celsius to Fahrenheit:

The conversion can be done in following 3 steps:

  • Multiply the temperature in degree with 9.
  • Divide the answer by 5.
  • Add 32 to the answer obtained in step 2.


Example 2: Convert 23°C to °F.

Solution: Following the above 3 steps one by one we get,

(23 x 9) = 207 and then

(207 ÷ 5) = 41.4 and then

41.4 + 32 = 71.4°F.


Maths class 3 Temperature


From this figure we can learn two things:

  • As the reading of thermometer increases the value of heat increases and hence the body becomes more hot.
  • As the reading of thermometer decreases the value of heat decreases and hence the body becomes more cold.

Maths class 3 Temperature


Points to Remember


  • The normal temperature of a human body is 37 degree Celsius.


Maths class 3 Temperature


  • The Celsius is marked from 0°C to 100°C.
  • The Fahrenheit scale is marked from 32°F to 212°F.
  • The thermometer used for the medical purpose has a special name Clinical Thermometer.

Practice Question

Q1) What is the normal temperature of a human body?

Q2) At which temperature water starts to boil?

Q3) Convert the following to Degree Fahrenheit.

  1. 0°C
  2. 100°C
  3. 37°C

Q4) State True or False:

  1. 1°C = 273 K
  2. Water freezes at 100°C.
  3. Temperature of ice is 0°C.



  • Thermometer is used to measure temperature of any body.
  • Unit of temperature can be K or °C or °F.
  • Temperature in °C = 273 – Temperature in K.
  • 0°C = 32°F.
  • Temperature of ice is 0°C or 32°F.
  • Doctors use Clinical Thermometer to measure temperature of patients.