1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
sashaice [31]
3 years ago
5

A thick oak wall initially at 25°C is suddenly exposed to gases for which T =800°C and h =20 W/m2.K. Answer the following questi

ons. Note: Evaluate the properties of the wall as cross grain oak at 300 K.
What is the surface temperature, in °C, after 400 s?
T (0,400 sec) =
Will the surface of the wall reach the ignition temperature of oak (400°C) after 400 s?
What is the temperature, in °C, 1 mm from the surface after 400 s? T (1 mm, 400 sec) =
Engineering
1 answer:
Schach [20]3 years ago
6 0

Answer:

a) What is the surface temperature, in °C, after 400 s?

   T (0,400 sec) = 800°C

b) Yes, the surface temperature is greater than the ignition temperature of oak (400°C) after 400 s

c) What is the temperature, in °C, 1 mm from the surface after 400 s?

   T (1 mm, 400 sec) = 798.35°C

Explanation:

oak initial Temperature = 25°C = 298 K

oak exposed to gas of temp = 800°C = 1073 K

h = 20 W/m².K

From the book, Oak properties are e=545kg/m³   k=0.19w/m.k   Cp=2385J/kg.k

Assume: Volume = 1 m³, and from energy balance the heat transfer is an unsteady state.

From energy balance: \frac{T - T_{\infty}}{T_i - T_{\infty}} = Exp (\frac{-hA}{evCp})t

Initial temperature wall = T_i

Surface temperature = T

Gas exposed temperature = T_{\infty}

You might be interested in
A large building will need several different types of workmen to install and repair pipes for water, heating,
siniylev [52]

Answer:

Plumber and pipefitters

Explanation:

3 0
3 years ago
Match each titration term with its definition.
Illusion [34]

Answer:

1) titration

2) titrand

3) equivalence point

4) titrant

5) Burette

6) Indicator

Explanation:

The process in which a known volume of a standard solution is added to another solution so that the standard solution can react with the solution of unknown concentration such that its concentration is determined  can be referred to as titration.

The solution which is added to another solution  is called the titrant.  The titrand is the solution of unknown concentration

A burette is a glassware used to slowly add a known volume of the titrant to the titrand.

The indicator used signals the point when the reaction is complete by a color change. At this point, a stoichiometric amount of titrant has been added to the titrand. This is also referred to as the equivalence point.

3 0
3 years ago
What are the maximum weights for single, tandem and 5-axle combinations?
belka [17]
Hauling Vehicles that include a semitrailer manufactured prior to or in the model year of 2024, and registered in Illinois prior to January 1, 2025, having 5 axles with a distance of 42 feet or less between extreme axles, may not exceed the following maximum weights: 20,000 pounds on a single axle; 34,000 pounds
7 0
3 years ago
Ben İngiliz oldum düzelte bilirmiyim
Lelu [443]

Answer:

What laguange is that?

Explanation:

7 0
3 years ago
If you need to write a function that will compute the cost of some candy, where each piece costs 25 cents, which would be an app
masya89 [10]
The best answer would be

D. Int calculateCost(int count);
6 0
3 years ago
Other questions:
  • If you know that the change in entropy of a system where heat was added is 12 J/K, and that the temperature of the system is 250
    10·1 answer
  • Please read
    6·1 answer
  • Assume a person is making a 350 mile trip from Amherst to Washington DC has four modes available to them: air; auto; train; ship
    10·1 answer
  • Under which of the following conditions is a Type B-1 Fire extinguisher required onboard a motorized vessel?
    14·2 answers
  • The Review_c object has a lookup relationship up to the Job_Application_c object. The job_Application_c object has a master-deta
    7·1 answer
  • In Engineering, what is a shoulder on a bridge?
    8·1 answer
  • A 0.39 percent Carbon hypoeutectoid plain-carbon steel is slowly cooled from 950 oC to a temperature just slightly below 723 oC.
    15·1 answer
  • The ultimate BOD of a river just below a sewage outfall is 50.0 mg/L, and the oxygen deficit at the outfall D0 is 2.0 mg/L. The
    6·1 answer
  • Limited time only for christmas give yourself free 100 points Thats what im talking about
    5·2 answers
  • 7. True or False? The positive effects of a new<br> technology always outweigh its negative effects.
    9·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!