Question -) Consider a stainless steel spoon (k = 15 W/m·K) partiallyimmersed in boiling water at 95°C in a kitchen at 25°C. Thehandle of the spoon has a cross section of 0.2cm x 1.2 cm, andextends 18 cm in the air from the free surface of the water. If theheat transfer coefficient at the exposed surfaces of the spoonhandle is 15 W/m2·°C, determine the temperature differenceacross the exposed surface of the spoon handle. State yourassumptions. SpoonQ3) Consider a stainless steel spoon (k = 15 W/m-K) partiallyimmersed in boiling water at 95°C in a kitchen at 25°C. The T=25°Chandle of the spoon has a cross section of 0.2cm x 1.2 cm, and18cmextends 18 cm in the air from the free surface of the water. If theheat transfer coefficient at the exposed surfaces of the spoonhandle is 15 W/m2.°C, determine the temperature difference Boilinacross the exposed surface of the spoon handle. State yourassumptions.water

Answered: Image /qna-images/answer/83b1d84c-af42-4e26-91bf-3d3ee06b926a.jpg

Consider a stainless steel spoon (k = 15 W/m·K) partially immersed in boiling water at 95°C in a kitchen at 25°C. The handle of the spoon has a cross section of 0.2cm x 1.2 cm, and extends 18 cm in the air from the free surface of the water. If the heat transfer coefficient at the exposed surfaces of the spoon handle is 15 W/m2·°C, determine the temperature difference across the exposed surface of the spoon handle. State your assumptions.

Consider a stainless steel spoon (k = 15 W/m·K) partially immersed in boiling water at 95°C in a kitchen at 25°C. The handle of the spoon has a cross section of 0.2cm x 1.2 cm, and extends 18 cm in the air from the free surface of the water. If the heat transfer coefficient at the exposed surfaces of the spoon handle is 15 W/m2·°C, determine the temperature difference across the exposed surface of the spoon handle. State your assumptions.

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 1.60P: 1.60 Two electric resistance heaters with a 20 cm length and a 2 cm diameter are inserted into a...

See similar textbooks

Similar questions

1.60 Two electric resistance heaters with a 20 cm length and a 2 cm diameter are inserted into a well-insulated 40-L tank of water that is initially at 300 K. If each heater dissipates 500 W, what is the time required for bringing the water temperature in the tank to 340 K? State your assumption for your analysis.
A glass container with an insulationg cover with a surface areaof (r+150) cm2 and (r+10) mm tick is filled with ice at 0 c and placed in a second vessel maintained at atemperature of (r+80)c. find the mass of the ice that melts per minute when the flow of heat becomes steady specific latent heat of ice=3.36*105 J/KG and k for glass is 1w /mk
A wall (3m * 2m) consist of 10 cm face brick with 15 cm concrete and 1.3 cm cement plaster . The outdoor temperature is -7°C . while the indoor space temperature is 24°C DBT and 10°C dew point temperature. Find (a)heat transfer (Q) through the wall ? (b) Will moisture condense on this wall ?
"Consider a heat engine with a piston chamber that has a diameter of 30 mm, a cold reservoir at 285 K and hot reservoir at 350 K. It is also equipped with a metal can cylinder that has a volume of 0.0002 m3. What is the total volume of air in the system if the metal can cylinder is in the hot reservoir and the measured pressure and height of the piston are 103850 Pa and 60 mm, respectively?" O 4.24x10-5 m3 O 4.25x10-2 m3 O 2,42x10-4 m3 O 3.70x10-4 m3
A 30-cm-radius metallic sphere is having thermal conductivity of k = 100. overall density of W 7 mk p = 1500- kg m² and heat capacity of C₂ = 3000 The sphere is initially at a uniform temperature of kgk CO T₁ = 20°C and is dropped into boiling water at T = 90°C. The convective heat transfer coefficient is assumed to be only h = 50; W m²K Using lump model, compute the temperature of the sphere after t = 1200 seconds. In solving this problem, please use and show the following steps (do not use EES) 1. Compute the volume and surface area 2. Compute the characteristic length Lc = k p Cp h Lc 4. Compute the Biot number Bi k 5. Calculate the Fourier number Fo= (at)/Lc² 6. Calculate the excess temperature using 0 = exp(-Bi * Fo) T-Too 7. Compute the target temperature T using 0 = Ti-Too 3. Compute the diffusivity a = = the sphere Vol Vol As == 3 r³ and А¸ = 4πr²
A long 3-mm diameter rod of steel (ρ = 7840 kg/m3, c = 460 J/kgK, k = 43 W/mK)has a uniform initial temperature of 650C. The rod is then suddenly immersed in alarge container of 25C water. The hot rod causes the water immediately surroundingthe rod to boil, giving rise to a heat transfer coefficient of 5600 W/m2K. The boilingstops when the rod reaches a temperature of 100C, at which time the heat transfercoefficient becomes 750 W/m2K. Find the time period during which boiling occursand the total time required for the rod to reach a temperature of 40C. Use acharacteristic length for this problem.
The condenser of a steam power plant operates at a pressure of 12.35 kPa. Steam at this pressure condenses on the outer surfaces of horizontal tubes through which cooling water circulates. The outer diameter of pipes is 4 cm, and the outer surfaces of the tubes are maintained at 20°C (see the figure). Determine: The rate of heat transfer to the cooling water circulating in the tubes, and The rate of condensation of steam per unit length of a horizontal tube. (45860.1 W, 36.3 kg/h)
The boiling temperature of oxygen at atmospheric pressure at sea level (1 atm) is -183ºC. Therefore, oxygen is used in low temperature scientific studies since the temperature of liquid oxygen in a tank open to the atmosphere remains constant at -183ºC until the liquid oxygen in the tank is depleted. Any heat transfer to the tank results in the evaporation of some liquid oxygen, which has a heat of vaporization of 213 kJ/kg and a density of 1140 kg/m3at 1 atm. Consider a 4 m diameter spherical tank initially filled with liquid oxygen at 1 atm and -183ºC. The tank is exosed to 20ºC ambient ait with a heat transfer coefficient of 25 W/m2. ºC. The temperature of the thin-shelled spherical tank is observed to be almost the same as the temperature of the oxygen inside. Disregarding any radiation heat exchange, determine the rate of evaporation of the liquid oxygen in the tank as a result of the heat transfer from the ambient air
H.W. Q: An aluminum pan whose thermal conductivity is 237 W/m-°C has a flat bottom with diameter 20 cm and thickness 0.4 cm. Heat is transferred steadily to boiling water in the pan through its bottom at a rate of 800 W. If the inner surface of the bottom of the pan is at 105°C, determine the temperature of the outer surface of the bottom of the pan. 105°C 0.4 cm Answer: T= 105.43 °C 800 W 7
A 2-kW resistance heater wire with thermal conductivity k = 15 W/m - °C, di- ameter D = 0.4 cm, and length L = 50 cm is used to boil water by immersing Water it in water (Fig. 2-19). Assuming the variation of the thermal conductivity of the wire with temperature to be negligible, obtain the differential equation that de- scribes the variation of the temperature in the wire during steady operation. Resistance heater
Thank you so much! I have one last follow up question. It is about heat transfer rate. Can you answer it too? It is shown in the screenshot:
• An aluminum pot contains water that is kept steadily boiling (100 °C). The bottom surface of the pot, which is 12 mm thick and 1.5x10t mm2 in area, is maintained at a temperature of 102°C by an electric heating unit. Find the rate at which heat is transferred through the bottom surface. Compare this with a copper based pot. Tc 0 0 L=12mm Base of pot TH A= area of base