Engineering
Physics
Conduction of Heat
Question

Entries in column I consists of diagrams of thermal conductors. The type of conductor & direction of heat flows are listed below. Entries in column II consists of the magnitude of rate of heat flow belonging to any of the entries in column I. If temperature difference in all the cases is (T1 – T2), then match column

Column I Column II
(P)  (1) 6πk0R(T1 – T2)
(Q)  (2) πk0R3ln2(T1T2)
(R)  (3) πk0R(T1 – T2)
(S)  (4) 4πk0Rln2(T1T2)

P-3, Q-1, R-4, S-2

P-3, Q-2, R-4, S-1

P-4, Q-3, R-2, S-1

P-1, Q-2, R-3, S-4

JEE Advance
College PredictorLive

Know your College Admission Chances Based on your Rank/Percentile, Category and Home State.

Get your JEE Main Personalised Report with Top Predicted Colleges in JoSA

Solution

(A)ΔQΔt=k0[π(2R)2πR2]3R(T1T2)=πRk0(T1T2)

(B)ΔQΔt=4πkR1R2(R2R1)(T1T2)=4πk03R·R(3RR)(T1T2)=6πk0R(T1T2)

(C)ΔQΔt=2πk0lln(R2R1)(T1T2)=4πk0Rln2(T1T2)

(D)ΔQΔt=πR2dTdx=πR2k0(1+x3R)dTdx

ΔQΔt=03Rdx(1+x3R)=πR2k0T1T2dt

ΔQΔt=ln(1+x3R)(R/3)|03R=πR2k0(T1T2)

ΔQΔt=πk0R(T1T2)3ln2