A long metallic bar is carrying heat from one of its ends to the other end under steady-state. The variation of temperature θ along the length x of the bar from its hot end is best described by which of the following figure. 

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B.

We know that 
In steady state flow of heat

One end of a thermally insulated rod is kept at a temperature T₁ and the other at T₂. The rod is composed of two sections of lengths

• (k₂

• (k₂

• (k₁

• (k₁A₁ T₁ + k₂A₂T₂) / (k₁A₁ + k₂A₂)

If C_p and Cv denote the specific heats of nitrogen per unit mass at constant pressure and constant volume respectively, then

• C_p – C_v = R/28

• C_p −C_v = R/14

• C_p −C_v = R

• C_p – C_v = 28 R

Assuming the sun to be a spherical body of radius R at a temperature of T K, evaluate the total radiant power, incident on Earth, at a distance r from the Sun.

where r₀ is the radius of the Earth and σ is Stefan’s constant

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C.