Heat Conduction in One Dimension

IMPORTANT

Heat Conduction in One Dimension: Overview

This topic covers concepts, such as Thermal Conduction, The Steady State Heat Flow, Heat Flow through Spherical Bodies & Heat Flow through Cylindrical Bodies etc.

Important Questions on Heat Conduction in One Dimension

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Graph shown below shows temperature variation inside the wall. The wall of a house is made of two different materials of same thickness. The temperature of the outer wall is T2 and that of inner wall is T1<T2. Then:

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  Which one is having the lowest thermal conductivity?

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What is the Searle's apparatus?

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What is Searle's method for thermal conductivity?

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Two heater coils separately take 10 min and 5 min to boil a certain amount of water. If both the coils are connected in series, the time taken to boil water is

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Cloudy nights are usually warmer than clear ones, because clouds 

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SI unit of temperature gradient is

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Which one of the following is not the example of the athermanous medium.

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Which one of the following is not the example of the diathermanous medium.

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Three rods (lengths 2l, l, l) made of the same material and having the same area of cross-section are joined as shown in figure. The end points A, B and C are maintained at constant temperatures 100°C, 50°C and 0°C, respectively. Assuming that there is no loss of heat from the surface of the rods, find the temperature that the junction P ultimately reaches.

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Three rods AB, BC and BD of same length l and cross-sectional area A are arranged as shown. The end D is immersed in ice whose mass is 440 g and is at 0C. The end C is maintained at 100°C. Heat is supplied at constant rate of 200 cal s-1. Thermal conductivities of AB, BC and BD are K, 2K and K2, respectively. Time after which whole ice will melt is K=100 cal/m-s-C, A=10 cm2, l=1 m

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In the given diagram, the possible direction of heat energy transformation is
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In steady state heat conduction, the equations that determine the heat current jr [heat flowing per unit time per unit area] and temperature Tr in space are exactly the same as those governing the electric field Er and electrostatic potential Vr with the equivalence given in the table below.

Heat flow Electrostatics
Tr Vr
jr Er
We exploit this equivalence to predict the rate Q of total heat flowing by conduction from the surfaces of spheres of varying radii, all maintained at the same temperature. If QRn, where R is the radius, then the value of n is

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A copper rod of length 2.5 m and an iron rod of length 1.5 m having the same areas of cross section are connected in series. Thermal conductivities of copper and iron are respectively 400 and 80 SI units. The equivalent conductivity of the composite bar in SI unit is ____.

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Heat is passed through two cylindrical rods of same material. Their diameters and lengths are in the ratio 1:2 and 2:1 respectively. If their ends are maintained at same temperature difference, the ratio of rate of flow of heat through them is

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The diameter of a rod is given by d=d0(1+ax) where a is a constant and x is the distance from one end. If the thermal conductivity of the material is K, what is the thermal resistance of the rod if length is l.
 

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What is the rate of flow of heat through a tapering rod of length tapering from radius r1 and r2, when the temperature of the ends are θ1°C and θ2C and coefficient of thermal conductivity is K?

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Three rods made of the same material and having same cross-sectional area but of different lengths 10 cm, 20 cm and 30 cm are joined as shown. The temperature of the junction is :-

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A metal rod of length 2 m has cross-sectional areas 2A and A as shown in the following figure. The two ends are maintained at temperatures 100°C and 70°C. The temperature of middle point C is:-

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On heating one end of a rod, the temperature of whole rod will be uniform when:-