Question
Physics Question on communication systems
A copper bar of length 1 m and cross-sectional area 10 × 10-2 m2 has its one end maintained at 100oC by means of 0.4 kW electric heater. What is the temperature of the other end in steady state, given that the thermal conductivity of copper is 400 W/mK?
A
(A) 60oC
B
(B) 70oC
C
(C) 80oC
D
(D) 90oC
Answer
(D) 90oC
Explanation
Solution
Explanation:
As,dQdt=KAd[TH−TC][dQdt]dKA=[TH−TC]⇒TC=TH−[dQdt]dKATC=100−400×1400×10×10−2=90∘C