$A$ thermocouple is an arrangement of two different metals to :-

$Assertion :$ Woolen clothes keep the body warm in winter.
$Reason :$ Air is a bad conductor of heat.

The quantity of heat which crosses unit area of a metal plate during conduction depends upon

The value of the temperature gradient is $80\,^{\circ}C/m$ on a rod of $0.5\,m$ length. If the temperature of the hot end is $30\,^{\circ}C$, what is the temperature of the cold end?

Two thin blankets keep more warmth than one blanket of thickness equal to these two. The reason is

The heat is flowing through a rod of length $50 \ cm$ and area of cross-section $5 \ cm^2$. Its ends are respectively at $25^\circ C$ and $125^\circ C$. The coefficient of thermal conductivity of the material of the rod is $0.092 \ kcal/m \cdot s \cdot ^\circ C$. The temperature gradient in the rod is