Solid objects, such as your desk or a rod of aluminum, can conduct heat. The magnitude of the thermal diffusivity of the material determines how quickly the heat moves through a given amount of material. The equation for thermal diffusivity (a) is given by:
Experiments are conducted to change the specific heat (Cp) of the material while holding the thermal conductivity (k) and the density (ρ) constant. The results are shown graphically.
- a. What are the units of the constant 0.088? Simplify your answer.
- b. If the thermal conductivity of the material is 237 watts per meter kelvin, what is the density of the material?
- c. If the material has a density of 4500 kilograms per cubic meter, what is the thermal conductivity of the material in units of watts per meter kelvin?
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- An electric heater producing 260 W of heat is used to warm up a room containing 7 m3 of air. If we assume the room is perfectly sealed and there is no heat loss through the room boundaries, such that all of the heater output goes into increasing the air temperature, how long will it take to heat up the air in the room from 5.0 °C to 24.1 °C? Give your answer to the nearest minute and assume that the specific volume (v = 0.85 m3/kg) and specific heat capacity at constant volume (cv = 1.005 kJ/(kg K)) remain constant throughout the heating process.arrow_forwardLiquid is held into two components Separated by a membrane.the total volume is 775ft3 and the volume of compartment Y is 300ft3 and it’s specific volume is 9.55ft3/lb.the membrane breaks and the resulting specific volume is 12.5 ft3/lb. a) determine the original specific volume in compartment X b)after breaking the membrane,the temperature of the liquid is 3 degree centigrade.if the absolute temperature of this reading is doubled and decreased by 239 degrees,what would be the final temperature of the maximum degree Celsius and degree Rankinearrow_forwardThe block in the drawing has dimensions L0×2L0×3L0,where L0 =0.5 m. The block has a thermal conductivity of 300 J/(s·m·C˚). In drawings A, B, and C, heat is conducted through the block in three different directions; in each case the temperature of the warmer surface is 36 ˚C and that of the cooler surface is 6 ˚C Determine the heat that flows in 6 s for each case.arrow_forward
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- Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning