Chapter 3, Problem 3.40P

When determining the specific heat of a metal specimen, what would happen to your experimental results if too much cold water were placed in the inner calorimeter cup with the metal specimen? Why?

The 5-mm-thick bottom of a 200-mm-diameter pan may be made from aluminum (k= 240 W/m·K) or copper (k= 390 W/m·K). When used to boil water, the surface of the bottom exposed to the water is nominally at 110°C and heat is transferred from the stove to the pan at a rate of 1200 W. What is the temperature of the surface in contact with the stove for each of the two materials?Aluminum:T= _____ °CCopper:T= _____ °C

Problem 1: Determine the amount of heat removed from 1.5 kg of bologna (sausage) when cooled from 24C to -7C.Assume MC of 59% and at -7C, 22% won’t be frozen. Problem 2: Estimate the thermal diffusivity of butter at 20°C.

You are interested in analyzing the rate at which a spherical ice ball melts. What heat equation should you use for the ice? List all assumptions.

Solve for this : An engine cover is made from 1 cm thick stainless steel plate (k = 14 W/m K). Air on the inside of the engine cover is heated to 340°C with a heat transfer coefficient of 7 W/m2K. Outside of the engine coverthe ambient air has a temperature of 70°C. If oil was spilled on the outside of the engine cover (ambient side), it could ignite if the surface temperature were to exceed 200°C. In this configuration, would spilled oil ignite? Use calculations to justify your answer. If a 4 mm thermal coating (k = 1.1 W/m K) was applied tothe outside of the engine, what would the outside temperature of the engine cover be reduced to?

For bacteriological testing of water supplies and in medical clinics, samples must routinely be incubated for 24 h at 37°C. Peace Corps volunteer and MIT engineer Amy Smith invented a low-cost, low-maintenance incubator. The incubator consists of a foam-insulated box containing a waxy material that melts at 37.0°C interspersed among tubes, dishes, or bottles containing the test samples and growth medium (bacteria food). Outside the box, the waxy material is first melted by a stove or solar energy collector. Then the waxy material is put into the box to keep the test samples warm as the material solidifies. The heat of fusion of the phase-change material is 205 kJ/kg. Model the insulation as a panel with surface area 0.490 m2, thickness 4.50 cm, and conductivity 0.012 0 W/m ? °C. Assume the exterior temperature is 23.0°C for 12.0 h and 16.0°C for 12.0 h. (a) What mass of the waxy material is required to conduct the bacteriological test? (b) Explain why your calculation can be done…

It is a problem of expansion and shrinkage of steel material so that the slightly smaller hole of a steel bushing of 1.999 diameter with the following process/materials/data to apply: Coefficient of expansion of carbon steel = 0.0000068 in/in-°F. Temperature raised by gas heating = 24.5 °F Cooling media to use dry ice with boiling point of -109.3 °F (-78.5 °C). Shrinkage rate below boiling point is 0.00073 in/in. Determine the final clearance between the expanded steel bushing hole against the shrinkage of the steel shaft. A. 0.000793 in B. 0.000693 in C. 0.000750 in D. 0.0008 in. Please solve elaborately and include the Units. Thank you dear, your solution will be appreciated much.

(a) The temperature at the surface of the heating rod, T1. (b) If the salt solution temperature is 300 degree Celcius, what is the value of convection heat transfer coefficient, h of the salt solution ? (c) If the heating rod is not covered by metallic cylinder and corresponds to the result of part (a) and (b), how much the rate of energy transfer to the salt solution ? (d) Compare and discuss the difference of heat transfer with and without the matallic cylinder.

A mass of ice at -4°C is needed to cool 115 kg of vegetables in a bunker for 24 hours. The initial temperature of the vegetables is assumed to be 29°C. It is also assumed that, within the 24-hr period, the average temperature inside the bunker is 7°C. If the heat gained per hour in the bunker is 30% of the heat removed to cool the vegetables from 29°C to 7°C, what would be the required mass of ice in kg? Use: Specific heat of water 4.2292 kJ/kg-°C Specific heat of ice 1.9387 kJ/kg °C Specific heat of vegetables 3.35 kJ/kg-°C