Two identical plates of different metals are joined to form a single plate whose thickness is double the thickness of each plate. If the coefficients of conductivity of each plate are 2 and 3 respectively, Then the conductivity of composite plate will be

Two identical plates with thermal conductivities K and 3K are joined together to form a single plate of double thickness. The equivalent thermal conductivity of one composite plate so formed for the flow of heat through its thickness is.

Two identical plates with thermal conductivities K and 3K are joined together to form a single plate of double thickness. The equivalent thermal conductivity of one composite plate so formed for the flow of heat through its thickness is.

If two metallic plates of equal thickness and thermal conductivities K_1 and K_2 ​are put together face to face and a common plate is constructed, then the equivalent thermal conductivity of this plate will be

IF two metallic plates of equal thickness and thermal conductivities K_(1) and K_(2) are put together face to face anda common plate is constructed, then the equivalent thermal conductivity of this plate will be

If two metallic plates of equal thickness and thermal conductivities K_(1) and K_(2) are put together face to face and a common plate is constructed, then the equivalent thermal conductivity of this plate will be

Two metal plates of same area and thickness l_(1) and l_(2) are arranged in series If the thermal conductivities of the materials of the two plates are K_(1) and K_(2) The thermal conductivity of the combination is .

Five identical plates each of area a are joined as shown in the figure. The distance between the plates is d. the plates are connected to a potential difference of V volt. The charge on plates 1 and 4 will be

Between the plates of a parallel plate capacitor of capacity C, two parallel plates of the same material and same area as the plates of the original capacitor are placed. If the thickness of each plate =(1)/(5) the distance between the plates of the original capacitor, then the capacity of the new capacitor will be