A 2-m-long, 4-cm-diameter electrical wire extends across a room at 20°C, as Shown in Fig. below. Heat is generated in the wire due to resistance heating, and the surface temperature of the wire is measured to be 252°C in steady operation. Also, the voltage drop and electric current through the wire are measured to be 80 V and 2 A, respectively. Heat loss transfer by radiation was 40 W from the surface of the 20 wire. Heat transfer coefficient for heat transfer between the outer surface of the wire and the air in the room. 2 A 80 V T 252 If the heat generation by electrical wire increased up to 200 W, what is the surface temperature of the wire, assuming no change in heat transfer coefficient?

A 2-m-long, 4-cm-diameter electrical wire extends across a room at 20°C, as Shown in Fig. below. Heat is generated in the wire due to resistance heating, and the surface temperature of the wire is measured to be 252°C in steady operation. Also, the voltage drop and electric current through the wire are measured to be 80 V and 2 A, respectively. Heat loss transfer by radiation was 40 W from the surface of the 20 wire. Heat transfer coefficient for heat transfer between the outer surface of the wire and the air in the room. 2 A 80 V T 252 If the heat generation by electrical wire increased up to 200 W, what is the surface temperature of the wire, assuming no change in heat transfer coefficient?

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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Concept explainers

Conduction and Convection

When energy travels from one object to another it is said to have undergone heat transfer. Heat transfer is nothing but the transfer of thermal energy or internal energy from one thing to another, like e.g., when a vessel with water, kept on top of a burner, heats up because of the flame underneath it.

Question

A 2-m-long, 4-cm-diameter electrical wire extends across a room at 20°C, as
Shown in Fig. below. Heat is generated in the wire due to resistance heating, and the
surface temperature of the wire is measured to be 252°C in steady operation. Also,
the voltage drop and electric current through the wire are measured to be 80 V and
2 A, respectively. Heat loss transfer by radiation was 40 W from the surface of the
wire. Heat transfer coefficient for heat
20 C
transfer between the outer surface of the
wire and the air in the room.
2
80 V
T 252
If the heat generation by electrical wire
increased up to 200 W, what is the surface temperature of the wire, assuming no
change
heat transfer coefficient?

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