When an object is removed from a furnace and placed in an environment with a constant temperature of 80°F, its core temperature is 1500°F. One hour after it is removed, the core temperatur (a) Write an equation for the core temperature y of the object t hours after it is removed from the furnace. (Round your coefficients to four decimal places.) y(t) = (b) Find the core temperature 8 hours after the object is removed from the furnace. (Round your answer to one decimal place.) oF

When an object is removed from a furnace and placed in an environment with a constant temperature of 80°F, its core temperature is 1500°F. One hour after it is removed, the core temperatur (a) Write an equation for the core temperature y of the object t hours after it is removed from the furnace. (Round your coefficients to four decimal places.) y(t) = (b) Find the core temperature 8 hours after the object is removed from the furnace. (Round your answer to one decimal place.) oF

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 1.22P: 1.22 In order to prevent frostbite to skiers on chair lifts, the weather report at most ski areas...

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3. A metallic rod 20 cm long is heated to a uniform temperature of 100° C. At t = 0 the ends of the bar are plunged into an ice bath at 0° C and thereafter maintained at this temperature. Find an expression for the temperature u(x, t) if the bar is made of cast iron. Material a (cm²/s) Silver 1.71 Copper 1.14 Aluminum 0.86 Cast iron 0.12 Granite 0.011 Brick 0.0038 Water 0.00144 Table 1: Thermal Diffusivity Constants for Common Materials
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A one-meter long bar has been heated unevenly, with temperature in °C at a distance z meters from one end at time t given by H(2, t) = 110e 0.06t sin(rz) 0 < <1. (a) On a sheet of paper, sketch a graph of H against z for t = 0 and t = 1. Use this graph to select all correct statements below. A. When t = 0, the rod is the same temperature throughout B. The rod is coldest at the r = 0 end, and warmest at the a = 1 and C. The two ends of the rod remain at 0°C D. The rod is coldest in the middle E. The middle of the rod gets colder over time F. The closer you are to the middle of the rod, the greater the temperature change from t = 0 to t = 1 G. None of the above %3D (b) On a sheet of paper, sketch a graph of H against t for a= 1/8, a= 1/4, and a = 1/2. Use this graph, and your observations from the previous graph, to select all correct statements below. JA. As time goes on, all part of the rod approach the same temperature B. The temperature near the middle of the rod changes most quicky…
The specific heat of copper is 0.093 cal/(g.°C) and the specific heat of gold is 0.031 cal/(g.°C). If 5.8 cal is supplied to one gram of copper and one gram of gold, the RATIO of temperature increase of gold to that of copper is
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Q1. The following data is obtained during geothermal drilling operation. Rock density = 1550 kg/m ³, heat capacity of the rock = 0.00163 J/kg K, temperature difference = 80 K. How much will be the thermal heat content of the rock at the geothermal site? Discuss about geothermal gradients their importance in energy exploration. Do you think utilization of geothermal energy worldwide is increasing yearly? Justify your answer. Do you think the geothermal energy available in this site can be used for a metal melting industry?
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