Page 1 - LN
P. 1

SAI International School
                                                   Class VII

                                               Lesson Notes
                                             Subject: Physics
                                       Ch-Heat and temperature
                                               Subtopic: Heat

         HEAT
         Heat is the form of energy which gives sensation of hotness or coldness in a object.
         S.I unit of heat is Joule (J).
         Calorie is the other unit of heat.
         1 calorie is the amount of heat energy required to raise the temperature of the 1 gram of
                          o
         water through 1 C.
         1 cal=4.2J

         Heat always flows from high temperature to low temperature.






















            Effects of heat:
                  Heat brings change in temperature.
                   Eg: Utensils on fire have high temperature.
                  Heat can bring change in dimensions such as increasing the temperature causes
                   change in length, area and volume.
                  Heat can change the state of substances.
   1   2