# The inner wall of a furnace is at a temperature of 700°C. The composite wall is made of two substances, 10 and 20 cm thick with thermal conductivities of 0.05 and 0.1 W.m-1.°C- 1 respectively. The ambient air is at 30°C and the heat transfer co-efficient between the outer surface of wall and air is 20 W.m-2.°C-1. The rate of heat loss from the outer surface in W.m-2is _____ ? with Answer - Chemical Engineering Mcqs | TestPrep

> Solved MCQ: The inner wall of a furnace is at a temperature of 700°C. The composite wall is made of two substances, 10 and 20 cm thick with thermal conductivities of 0.05 and 0.1 W.m-1.°C- 1 respectively. The ambient air is at 30°C and the heat transfer co-efficient between the outer surface of wall and air is 20 W.m-2.°C-1. The rate of heat loss from the outer surface in W.m-2is _____ ? Correct Answer: A. 165.4. Verified answer explanation for FPSC, PPSC, MDCAT, NTS, and CSS competitive exam preparation.

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# The inner wall of a furnace is at a temperature of 700°C. The composite wall is made of two substances, 10 and 20 cm thick with thermal conductivities of 0.05 and 0.1 W.m-1.°C- 1 respectively. The ambient air is at 30°C and the heat transfer co-efficient between the outer surface of wall and air is 20 W.m-2.°C-1. The rate of heat loss from the outer surface in W.m-2is _____ ?

Direct Answer & Quick Reference

The correct option is **A. 165.4**.

A. 165.4 **(Correct Answer)**

B. 167.5

C. 172.5

D. 175

✨ Explain with AI

Verified Key: A. 165.4
Solved by 5,316+ students

Verified against official examination board answer keys and standard curriculum textbooks.

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