wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

Two rod of same length and same diameter are drawn from equal masses and same quantity of heat I is supplied to the rods. If the are rods joined together to 100 oC and 40 oC at the ends, find ratio of their conductivities.

Open in App
Solution

The two rods have same length L and same cross-sectional A(=πD24) but different conductivities K1 & K2, joined in series:- [Ref. above image]
The current (I=dQdt,Q:Heat supplied) is constant in series convection.
The conductivity in series (equivalent) would be:
K=K1K2K1+K2 [A,L are same]
We can write,
I=K(ΔT), where ΔT : Temp. difference
K=IΔT=I10040=I60.
Thus, K1K2K1+K2=I6060K1K2=IK1+IK2
which given ratio:
K1K2=60I60

1061130_1163050_ans_6f4db96f01b042f3b00595ccdcbd88e0.png

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Dimensional Analysis
PHYSICS
Watch in App
Join BYJU'S Learning Program
CrossIcon