A radioactive sphere of 20-cm diameter generates heat at the rate of 300 W. It is cooled by placing in a cold inert fluid. The fluid temperature is –20°C. At steady state, the surface temperature of the sphere was found to be 20°C. What is the heat transfer rate from the sphere?

A radioactive sphere of 20-cm diameter generates heat at the rate of 300 W. It is cooled by placing in a cold inert fluid. The fluid temperature is –20°C. At steady state, the surface temperature of the sphere was found to be 20°C. What is the heat transfer rate from the sphere?

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.82P: Discuss the modes of heat transfer that determine the equilibrium temperature of the space shuttle...

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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 radioactive sphere of 20-cm diameter generates heat at the rate of 300 W. It is cooled by placing
in a cold inert fluid. The fluid temperature is –20°C. At steady state, the surface temperature of
the sphere was found to be 20°C. What is the heat transfer rate from the sphere?

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