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
UkoKoshka [18]
3 years ago
11

An Ideal gas is being heated in a circular duct as while flowing over an electric heater of 130 kW. The diameter of duct is 500

mm. The gas enters the heating section of the duct at 100 kPa and 27 deg C with a volume flow rate of 15 m3/s. If heat is lost from the gas in the duct to the surroundings at a rate of 80 kW, Calculate the exit temperature of the gas in deg C. (Assume constant pressure, ideal gas, negligible change in kinetic and potential energies and constant specific heat; Cp =1000 J/kg K; R = 500 J/kg K)
Engineering
1 answer:
Rashid [163]3 years ago
6 0

Answer:

Exit temperature = 32 °C

Explanation:

We are given;

Initial Pressure;P1 = 100 KPa

Cp =1000 J/kg.K = 1 KJ/kg.k

R = 500 J/kg.K = 0.5 Kj/Kg.k

Initial temperature;T1 = 27°C = 273 + 27K = 300 K

volume flow rate;V' = 15 m³/s

W = 130 Kw

Q = 80 Kw

Using ideal gas equation,

PV' = m'RT

Where m' is mass flow rate.

Thus;making m' the subject, we have;

m' = PV'/RT

So at inlet,

m' = P1•V1'/(R•T1)

m' = (100 × 15)/(0.5 × 300)

m' = 10 kg/s

From steady flow energy equation, we know that;

m'•h1 + Q = m'h2 + W

Dividing through by m', we have;

h1 + Q/m' = h2 + W/m'

h = Cp•T

Thus,

Cp•T1 + Q/m' = Cp•T2 + W/m'

Plugging in the relevant values, we have;

(1*300) - (80/10) = (1*T2) - (130/10)

Q and M negative because heat is being lost.

300 - 8 + 13 = T2

T2 = 305 K = 305 - 273 °C = 32 °C

13000 + 300 - 8000 = T2

You might be interested in
If 1 uF capacitor is fully charged with 120 V across it, how much energy is stored in it? (a) 7.2 kJ (b) 7.2 mJ (c) 0.12 mJ (d)
jeyben [28]

Answer:

(b) 7.2 mJ

Explanation:

ENERGY STORED IN CAPACITOR: the energy is stored in capacitor in electric field

which can be calculated by expressions

E=\frac{1}{2} c v{^2}

=\frac{1}{2} 10^{-6}120^{2}

=7200×10^{-6} J

= 7.2×10^{-3} J

=7.2 mJ

4 0
3 years ago
To put out a class D metal fire, you must _______ the fire.
gladu [14]

To put out a class D metal fire, you must smother the fire and eliminate the oxygen element in the fire.

<h3>What is a Class D fire?</h3>

A class D fire is a type of fire that cannot be extinguished by water. This is because adding water to it reacts with other elements in the fire intensifying the fire even more.

Smothering in this context involves adding a solution like carbon dioxide (CO2) into the fire, this results in a reduction of oxygen in the atmosphere surrounding the class D fire.

By so doing, smothering the fire eliminates the oxygen element in the fire, thereby extinguishing the fire.

You can learn more about extinguishing fires here https://brainly.in/question/760550

#SPJ1

7 0
2 years ago
For each of the resistors shown below, use Ohm's law to calculate the unknown quantity, Be sure to put your answer in proper eng
daser333 [38]

Answer:

the hurts my brain sorry bud cant help

Explanation:

6 0
3 years ago
Ann’s Retail, a women’s clothing store, hires female attendants to assist clients in the store’s dressing rooms. Larry, a male,
mojhsa [17]

Answer:

A bona fide occupational qualification defense

Explanation:

Since the store is for women clothing, the retail may prefer to employ only female to assist the customers.  Under a bona fide occupational qualification defense, an employer is allowed to discriminate if a characteristic is a necessity for the performance of the job and for the business. Therefore, the store has a bona fide occupational qualification defense.

3 0
3 years ago
The coupling is used to connect the two shafts together. Assuming that the shear stress in the bolts is uniform, determine the n
AleksAgata [21]

Answer:

n = 2r³/Rd²

Explanation:

See the attached file for the derivation.

8 0
3 years ago
Other questions:
  • When a mesh in a circuit contains an independent or dependent current source, this leads to a special case of mesh-current analy
    14·1 answer
  • What are the four processes of the Carnot cycle? Sketch the Carnot cycle (a) on T-s (temperature - entropy) and P-V (pressure -
    7·1 answer
  • Extra Credit: The Linc (parking lot and stadium)In celebration of the upcoming Super Bowl, for a maximum 10 points of extra cred
    7·1 answer
  • 3. When performing overhead work on scaffolding, what protective measures must be taken to prevent objects
    9·1 answer
  • A pool of contaminated water is lined with a 40 cm thick containment barrier. The contaminant in the pit has a concentration of
    11·1 answer
  • What structure was created to help prevent shipwrecks?
    9·1 answer
  • Can some one help me with this plumbing question. Even just a guess.<br> Plz no shady links
    11·2 answers
  • The volume of the pyramid is 36 cubic cm, find the volume of the prism.
    5·1 answer
  • Write down the three formula to find the three types of slope of curve Q with respect to L.
    5·2 answers
  • Which one of the following best defines hardness: (a) energy absorbed by a material when an object strikes its surface, (b) resi
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!