Question 31 of 126
Three rods of identical cross-section and length are made of three different materials of thermal conductivity and , respectively. They are joined together at their ends to make a long rod (see figure). One end of the long rod is maintained at and the other at (see figure). If the joints of the rod are at and in steady and there is no loss of energy from the surface of the rod, the correct relationship between and is :
Show answer and solution
Answer: (A) ,
.%20One%20end%20of%20the%20long%20rod%20is%20maintained%20at%20100%5E%C2%B0C%20and%20the%20other%20at%200%5E%C2%B0C%20(see%20figure).%20If%20the%20joints%20of%20the%20rod%20are%20at%2070%5E%C2%B0C%20and%2020%5E%C2%B0C%20in%20steady%20and%20there%20is%20no%20loss%20of%20energy%20from%20the%20surface%20of%20the%20rod%2C%20the%20correct%20relationship%20between%20K1%2CK2%20and%20K3%20is%20%3A%20%3Cimg%20src%3D%22%2Fpractice%2Fpyq%2Fthermal-properties-of-matter291097.png%22%3E%0A(A)%20K1%3AK3%3D2%3A3%2C%20K2%3AK3%3D2%3A5%0A(B)%20K1%20K2%20K3%0A(C)%20K1%3AK2%3D5%3A2%2C%20K1%3AK3%3D3%3A5%0A(D)%20K1%20K2%20K3){kind=link}