Heat and its unit

Heat:-
It is a form of energy. Heat energy can be transformed into other forms of energies. Heat flows from a hotter body to a colder body. 

Units of heat:-

Calorie:- It is the quantity of heat required to raise the temperature of 1 gram of water through 1°C.

Kilo calorie :- It is the quantity of heat required to raise the temperature of 1 kilo gram of water through 1°C.
1 kilo calorie = 1000 calories

B.Th.U:- It is the quantity of heat required to raise 1 lb of water
through 1°F. (British thermal unit).
1 B.Th.U= 252 calorie

C.H.U :- It is the quantity of heat required to raise 1 lb of water through 1°C.( centigrade heat unit).
Joule : S.I. Unit (1 Calorie = 4.186 joule)
1C.H.U = 453.6 calorie
1 C.HC. = 9/5 B.Th.U
              = 1.8 B.Th.U
Calorimeter :- The instrument used to measure heat is called calorimeter.

Effects of heat:-
• Change in temperature
• Change in size
• Change in state
• Change in structure
• Change in Physical properties

Specific heat :-
The quantity of heat required to raise the temperature of one gm of a substance through 10°C is called specific heat. It is denoted by the letter ‘s’.
Specific heat of water = 1
Aluminium = 0.22
Copper = 0.1
Iron = 0.12

Thermal capacity:-
It is the amount of heat required to raise the temperature of
a substance through 10°C is called the thermal capacity of
the substance.
Thermal capacity = ms calories.