Fundamentals of Heat and Mass Transfer
7th Edition
ISBN: 9780470917855
Author: Bergman, Theodore L./
Publisher: John Wiley & Sons Inc
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Chapter 5, Problem 5S.3P
To determine
The speed at which the rods must be drawn through the oven.
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Number 4
A food product wants to be produced in a small round shape (pellet) by freezing it in a water blast freezer freezer. Air
freezer operates at a temperature of -35 ° C. The initial product temperature is 25 ° C. The pellet has a diameter of
1.2 cm, and a density of 980 kg / m³. The initial freezing temperature is -2.5 ° C. The latent heat of freezing of the
product is 280 kJ / kg. The thermal conductivity of the frozen product is 1.9 W / (m ° C). The convective heat
transfer coefficient is 50 W / (m² K). Calculate the freeze time. identify :
a. tf = Answer in hour
Let's say a 3.0 gram copper wafer is dropped from a height of 50.0 meters. If 60% of the potential energy lost in the drop could be converted to thermal energy used to heat the copper from an initial temperature
of 25 degrees celsius, what would the final temperature of the copper wafer?
Would the answer be different if the wafer has a mass greater than 3 grams?
Note: the specific heat of copper is 387 J/(kg*K).
The temperature is between 25.8 and 26.0 degrees celsius, yes the bigger the mass the greater the energy.
O The temperature is between 25.6 and 25.8 celsius, answer does not depend on mass.
O The temperature is between 25.0 and 25.2 celsius, answer does not depend on mass.
O The temperature is 25.5 and of course the more mass something has the greater energy will be needed to raise the temperature.
The temperature is 26.2 and if the mass is doubled so will be the change in temperature.
O The temperature is 25.9 degrees celsius and the answer does not depend on mass.
O The…
In the vulcanization of tires, the carcass is placed into a jig and steam at 149°C is admitted
suddenly to both sides. If the tire thickness is 2.5 cm, the initial temperature is 21°C, the
heat transfer coefficient between the tire and the steam is 150 W/(m2 K), and the specific
heat of the rubber is 1650 J/(kg K), estimate the time required for the center of the rubber
to reach 132°C
Chapter 5 Solutions
Fundamentals of Heat and Mass Transfer
Ch. 5 - Consider a thin electrical heater attached to a...Ch. 5 - The inner surface of a plane wall is insulated...Ch. 5 - A microwave oven operates on the principle that...Ch. 5 - A plate of thickness 2L, surface area As, mass M,...Ch. 5 - For each of the following cases, determine an...Ch. 5 - Steel balls 12 mm in diameter are annealed by...Ch. 5 - Consider the steel balls of Problem 5.6, except...Ch. 5 - The heat transfer coefficient for air flowing over...Ch. 5 - A solid steel sphere (AISI 1010), 300 mm in...Ch. 5 - A flaked cereal is of thickness 2L=1.2mm. The...
Ch. 5 - The base plate of an iron has a thickness of L=7mm...Ch. 5 - Thermal energy storage systems commonly involve a...Ch. 5 - A tool used for fabricating semiconductor devices...Ch. 5 - A copper sheet of thickness 2L=2mm has an initial...Ch. 5 - Carbon steel (AISI 1010) shafts of 0.1-m diameter...Ch. 5 - A thermal energy storage unit consists of a large...Ch. 5 - Small spherical particles of diameter D=50m...Ch. 5 - A spherical vessel used as a reactor for producing...Ch. 5 - Batch processes are often used in chemical and...Ch. 5 - An electronic device. such as a power transistor...Ch. 5 - Molecular electronics is an emerging field...Ch. 5 - A plane wall of a furnace is fabricated from plain...Ch. 5 - A steel strip of thickness =12mm is annealed by...Ch. 5 - In a material processing experiment conducted...Ch. 5 - Plasma spray-coating processes are often used to...Ch. 5 - The plasma spray-coating process of Problem 5.25...Ch. 5 - A chip that is of length L=5mm on a side and...Ch. 5 - Consider the conditions of Problem 5.27. In...Ch. 5 - A long wire of diameter D=1mm is submerged in an...Ch. 5 - Consider the system of Problem 5.1 where the...Ch. 5 - Shape memory alloys (SMAs) are metals that undergo...Ch. 5 - Before being injected into a furnace, pulverized...Ch. 5 - As noted in Problem 5.3, microwave ovens operate...Ch. 5 - A metal sphere of diameter D, which is at a...Ch. 5 - A horizontal structure consists of an LA=10...Ch. 5 - As permanent space stations increase in size....Ch. 5 - Thin film coatings characterized by high...Ch. 5 - A long. highly polished aluminum rod of diameter...Ch. 5 - Thermal stress testing is a common procedure used...Ch. 5 - The objective of this problem is to develop...Ch. 5 - In thermomechanical data storage, a processing...Ch. 5 - The melting of water initially at the fusion...Ch. 5 - Consider the series solution, Equation 5.42, for...Ch. 5 - Consider the one-dimensional wall shown in the...Ch. 5 - Copper-coated, epoxy-tilled fiberglass circuit...Ch. 5 - Circuit boards are treated by heating a stack of...Ch. 5 - A constant-property, one-dimensional plane slab of...Ch. 5 - Referring to the semiconductor processing tool of...Ch. 5 - Annealing is a process by which steel is reheated...Ch. 5 - Consider an acrylic sheet of thickness L=5mm that...Ch. 5 - The 150-mm-thick wall of a gas-fired furnace is...Ch. 5 - Steel is sequentially heated and cooled (annealed)...Ch. 5 - Stone mix concrete slabs are used to absorb...Ch. 5 - During transient operation, the steel nozzle of a...Ch. 5 - Two plates of the same material and thickness L...Ch. 5 - In a tempering process, glass plate, which is...Ch. 5 - The strength and stability of tires may be...Ch. 5 - A plastic coating is applied to wood panels by...Ch. 5 - A long rod of 60-mm diameter and thermophysical...Ch. 5 - A long cylinder of 30-mm diameter, initially at a...Ch. 5 - A long pyroceram rod of diameter 20 mm is clad...Ch. 5 - A long rod 40 mm in diameter, fabricated from...Ch. 5 - A cylindrical stone mix concrete beam of diameter...Ch. 5 - A long plastic rod of 30-mm diameter...Ch. 5 - As part of a heat treatment process, cylindrical,...Ch. 5 - In a manufacturing process, long rods of different...Ch. 5 - The density and specific heat of a particular...Ch. 5 - In heat treating to harden steel ball bearings...Ch. 5 - A cold air chamber is proposed for quenching steel...Ch. 5 - Stainless steel (AISI 304) ball bearings. which...Ch. 5 - A sphere 30 mm in diameter initially at 800K is...Ch. 5 - Spheres A and B are initially at 800K. and they...Ch. 5 - Spheres of 40-mm diameter heated to a uniform...Ch. 5 - To determine which parts of a spider's brain are...Ch. 5 - Consider the packed bed operating conditions of...Ch. 5 - Two large blocks of different materials. such as...Ch. 5 - A plane wall of thickness 0.6 m (L=0.3m) is made...Ch. 5 - Asphalt pavement may achieve temperatures as high...Ch. 5 - A thick steel slab...Ch. 5 - A tile-iron consists of a massive plate maintained...Ch. 5 - A simple procedure for measuring surface...Ch. 5 - An insurance company has hired you as a consultant...Ch. 5 - A procedure for determining the thermal...Ch. 5 - A very thick slab with thermal diffusivity...Ch. 5 - Standards for firewalls may be based on their...Ch. 5 - It is well known that, although two materials are...Ch. 5 - Two stainless steel plates...Ch. 5 - Special coatings are often formed by depositing...Ch. 5 - When a molten metal is cast in a mold that is a...Ch. 5 - Joints of high quality can be formed by friction...Ch. 5 - A rewritable optical disc (DVD) is formed by...Ch. 5 - Ground source heat pumps operate by using the...Ch. 5 - To enable cooking a wider range of foods in...Ch. 5 - Derive an expression for the ratio of the total...Ch. 5 - The structural components of modem aircraft are...Ch. 5 - Consider the plane wall of thickness 2L, the...Ch. 5 - Problem 4.9 addressed radioactive wastes stored...Ch. 5 - Derive an expression for the ratio of the total...Ch. 5 - Prob. 5.107PCh. 5 - Prob. 5.108PCh. 5 - A thin rod of diameter D is initially in...Ch. 5 - A one-dimensional slab of thickness 2L is...Ch. 5 - Prob. 5.114PCh. 5 - Prob. 5.115PCh. 5 - A molded plastic product...Ch. 5 - Prob. 5.133PCh. 5 - A thin circular disk is subjected to induction...Ch. 5 - Two very long (in the direction normal to the...Ch. 5 - Prob. 5S.2PCh. 5 - Prob. 5S.3PCh. 5 - Estimate the time required to cook a hot dog in...Ch. 5 - Prob. 5S.7PCh. 5 - Prob. 5S.9PCh. 5 - Prob. 5S.10PCh. 5 - Prob. 5S.11PCh. 5 - Prob. 5S.13P
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