Question

On what factors does the amount of heat flowing in a substance depends? obtain the expression for the heat conducted

Answer 1

Heat flowing in a substance depends upon factors ,
(1) mass of the substance . higher the mass of substance , heat gaining will be higher . Means heat flowing in substance is directly proportional to mass of the body . e.g., Q α m , here Q is heat and m is mass of substance

(ii) temperature change , if Body is at higher temperature than surrounding it means body has higher heat than surrounding . Means increases the temperature , increases the heat flowing in a substance. or you can say that heat flowing in a substance is directly proportional to temperature change.
e.g., Q α ∆T , here ∆T is temperature change

(iii) heat also depends upon nature of substance, for example , at same temperature and same mass of water and petrol , water gain higher energy than petrol , due to high specific heat capacity of water than petrol.

(iv) phase of substance , heat flowing in substance also depends upon phase .
for example , heat of water is higher than ice , at same temperature and same mass . Q = 4200m∆T , for water [S = 4200 Cal/g/°C]
Q' = 2100m∆T [S'=2100 Cal/g/°C ], for ice , then you can see Q > Q'

Now, derivation of expression ,
Qαm∆T
⇒Q = Sm∆T
Here, S is proportionality constant known as specific heat capacity.
So, expression is Q = mS∆T