MCQ
Four rods of same material and having the same cross section and length have been joined, as shown. The temperature of junction of four rods will be........ $^oC$
- A$20$
- B$30$
- ✓$45$
- D$60$
✓
Answer
Correct option: C.
$45$
c
$\frac{{{\rm{KA}}(90 - \theta )}}{l} = \frac{{{\rm{KA}}(\theta - 30)}}{l} + \frac{{{\rm{KA}}(\theta - {\rm{0}})}}{l} + \frac{{{\rm{KA}}(\theta - 60)}}{l}$
$\frac{{{\rm{KA}}(90 - \theta )}}{l} = \frac{{{\rm{KA}}(\theta - 30)}}{l} + \frac{{{\rm{KA}}(\theta - {\rm{0}})}}{l} + \frac{{{\rm{KA}}(\theta - 60)}}{l}$
$90-\theta=3 \theta-90^{\circ}$
$\theta=45^{\circ}$ $C$
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