The quantity d t/Q for conduction of heat through a body i.e. spherica

1.	The quantity d t/Q for conduction of heat through a body i.e. spherical in shape is
A.	ln (r2/r1)/2πLk
B.	ln (r2/r1)/πLk
C.	ln (r2/r1)/2Lk
D.	ln (r2/r1)/2πk
Answer» B. ln (r2/r1)/πLk

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The quantity d t/Q for conduction of heat through a body i.e. spherical in shape is

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